ADU Permit Fees by City: 6 Cities Itemized (2026)

By The Dwelling Index Editorial Team · Updated September 2026

Compare ADU permit fees by city in six itemized examples below. San Diego's base plan-check and inspection fees for a new detached ADU rise from $5,741.21 at 500 fee-counted square feet to $16,487.16 at 501 — a $10,745.95 step, according to The Dwelling Index's September 2026 analysis of the city's fee schedule.

An ADU, or accessory dwelling unit, is a second, smaller home on the same lot as a house: a backyard cottage, a garage apartment, or a unit attached to the main home.

Compare the six cities · Check the headline calculation · Download the CSVs · Copy the citation

Key ADU permit fee statistics

1. $10,745.95: In San Diego, base plan-check and inspection fees for a new detached ADU are $5,741.21 up to 500 square feet and $16,487.16 from 501 to 3,000 square feet, a 187.2% jump. The city measures to the outside of the walls and adds counted accessory areas, such as patio covers and decks. (The Dwelling Index analysis of San Diego Information Bulletin 501, August 2026 edition)
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2. $9,601.95: In San Diego, an attached ADU with 600 fee-counted square feet has a modeled $6,885.21 in base plan-check and inspection fees; the same fee area built detached has $16,487.16. (The Dwelling Index analysis of San Diego Information Bulletin 501, August 2026 edition)
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3. $1,812: San José's listed ADU issuance, plan-review and inspection fees rise from $3,291 (up to 750 square feet) to $5,103 (751 to 1,200 square feet), a 55.1% jump. (The Dwelling Index analysis of San José's FY 2026-27 Building Division Fee Schedule, August 2026 schedule)
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4. Six-city base fees: Modeled building-permit or inspection plus plan-review fees for a new detached ADU are $1,186.03 in Austin, $2,341.81 in Portland, $894.90 in Raleigh, $16,487.16 in San Diego, $2,869.00 in San José and $4,418.00 in Seattle. Austin, San Diego and San José are figured at 600 fee-counted square feet; Portland, Raleigh and Seattle at a $150,000 city-set project value. (The Dwelling Index analysis of each city's current fee schedule, checked Sept. 29, 2026; different inputs and fee bundles, not an all-in ranking)
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5. 750 square feet: Since Jan. 1, 2026, California bars impact fees on an ADU with 750 square feet of interior livable space or less; bigger ADUs can be charged only in proportion to the main house's size. Utility connection fees and capacity charges don't count as impact fees under the same law. (Cal. Gov. Code §66311.5(c))
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6. 500 square feet and $5.38: California ADUs under 500 square feet of interior livable space don't pay school impact fees (since Jan. 1, 2026). For nonexempt projects, the state's Level 1 cap since Jan. 28, 2026 is $5.38 per square foot of assessable space — $4,035 at 750 assessable square feet, before any credits. Assessable space is a separate legal measurement, not automatically interior living space; higher fee levels have separate rules. (Gov. Code §66311.5(c)(3); State Allocation Board; assessable-space definition)
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7. 23%: In Portland's official sample for a new detached ADU, permit-related lines, including processing and surcharges, are $8,439.91 of the published $36,720.91 sample total; system development charges are 52% and a new water service is 22%. The sample uses July 1, 2023 rates and lists a waiver-application charge alongside SDCs; it is not a paid invoice. (The Dwelling Index analysis of City of Portland sample fees)
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8. $5,347.14: Sacramento's own ADU fee estimate, revised July 12, 2026, adds three impact fees totaling $5,347.14 at 750 square feet, within its $10,624.40 estimate at 750 square feet, compared with $5,271.90 at 749. The sheet does not identify its area as interior livable space, so this is a source discrepancy to resolve, not a current fee quote. (City of Sacramento form CDD-0419)
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9. $460.10: San José charges modular ADUs 10% less for plan review and 20% less for inspection, which takes $460.10 off the listed fees for a 600-square-foot ADU. (The Dwelling Index analysis of San José's FY 2026-27 fee schedule)
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10. 18.7%: Seattle's own permit-and-review example for a 500-square-foot detached ADU, valued at $93,145 in both years, rose from $2,908 in 2025 to $3,453 in 2026. (Seattle SDCI, 2026 Fee Changes)
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11. $6,472.45: Riverside County's base building-permit deposit for an ADU is the same as its deposit for a new single-family house. (Riverside County TLMA fee schedules, checked Sept. 29, 2026)
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12. First two ADUs: The City of San Diego exempts the first two ADUs on a lot from its development impact fees, whatever their size. (City of San Diego, SDMC §142.0640(b)(1))
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On this page: Fees in six cities · Where size changes the fee · California's 750 and 500 lines · What else is on the bill · Modular ADUs · City-by-city notes · What changed in 2026 · How we built this · How to cite · Data · FAQ

How much are ADU permit fees in each city?

For a new detached ADU, our modeled two-fee sums run from $894.90 in Raleigh to $16,487.16 in San Diego. Three examples use fee-counted floor area and three use a dollar value accepted by the city, so each row shows the input we used. These are two named fees, not the whole bill.

Say you're adding a backyard cottage with 600 square feet under the local fee-area rule. In Austin, the city's base building and review fees come to $1,186.03. In San Diego, the same size lands in the fee row the city uses for a whole new house or duplex: $16,487.16.

That's not a typo. And in neither city is it the whole bill.

What do these numbers include, and what do they leave out?

Each number adds the two fees every city prints: the building permit (or inspection) fee and the plan-review fee. Cities put different work inside those two fees.

San Diego's bulletin says its separate electrical, mechanical and plumbing fee schedule is for apartment and commercial jobs, or for house jobs with no building permit. Austin lists those trade permits on their own lines. So a low number can mean fewer things are bundled in, not a cheaper city.

Left out everywhere: impact fees, school fees, water and sewer hookups, and anything your lot triggers, like tree or floodplain review. The “Also listed” column shows examples of charges outside the two-fee sum. It is not a complete list.

Why do some cities charge by square feet and others by dollars?

The city picks the rule. Austin, San Diego and San José charge by floor area. Portland, Raleigh and Seattle charge a sliding amount based on the project's value.

Use the value the city accepts for fees. Raleigh and Seattle use construction-value tables; Raleigh's guide says a bid above or below its table value doesn't change that value. Portland instead uses the greater of its calculated table value and the applicant's stated value. (Portland schedule, page 1)

We used $150,000 as a stand-in value for those three cities. It is not a claim about what a 600-square-foot ADU is worth. For the dwelling alone, Raleigh's listed residential construction types give a value below $120,000 at 600 square feet after its regional adjustment. That would produce lower modeled base fees than our $150,000 row; added project scope still needs its own value.

Look up a city

Pick a city and enter the size or value the city uses. The lookup shows each fee from that city's current schedule, the base total, the other fees the schedule prints, and what's still missing. For San Diego and San José, enter interior livable space to check the state size exemptions. School-fee estimates need a separate assessable-space input.

Where does one square foot change the fee?

Two size lines stand out in the fee tables we checked. San Diego's base fees for a detached ADU jump $10,745.95 at 501 square feet, and San José's listed fees rise $1,812 at 751 square feet.

San Diego: what happens at 501 square feet?

San Diego's fee table puts a detached ADU of up to 500 square feet in its addition-and-remodel row, at $5,741.21 in base plan-check and inspection fees. From 501 to 3,000 square feet, the ADU moves to the row for new houses and duplexes, at $16,487.16.

Put simply: where the city charges $1 at 500 square feet, it charges $2.87 at 501.

The catch is how San Diego measures. Its fee area runs to the outside of the walls. It also counts roofed areas without walls, like a covered balcony. For houses and ADUs, it adds attached or detached extras such as patio covers, decks, storage and carports.

Say you plan a 470-square-foot cottage with a small covered porch. Add the wall thickness and the porch, and the city may count more than 500 square feet. If it does, the base fees nearly triple. Ask your designer for the fee area, figured the city's way, before you lock the plan.

Attached ADUs use a different fee row. San Diego's addition row names attached ADUs up to 1,100 fee-counted square feet, charging the base rate to 500 plus $6.98 per extra square foot for plan check and $4.46 for inspection. The row also names junior ADUs, but that is not permission to build a junior ADU with 1,100 square feet of living space.

One more San Diego fact keeps this in proportion: these big numbers aren't impact fees. The city exempts the first two ADUs on a lot from its development impact fees, whatever their size (City of San Diego FAQ). For the steps that come with the permit, see our San Diego ADU permit process guide.

San José: what happens at 751 square feet?

San José's ADU fee table has two size bands. Its listed issuance, plan-review and inspection fees total $3,291 for an ADU up to 750 square feet and $5,103 from 751 to 1,200 square feet, a $1,812 rise.

That's $1.55 for every $1, one square foot later.

Two notes keep this honest. First, these examples use the standard table amounts. The schedule compares them with $211 an hour for issuance, $325 for plan review and $315 for inspection, charging more when the hours cost more. Its Online Permits service has a separate issuance-minimum rule that we have not applied. Second, the issuance fee includes the new address, and the inspection fee includes the meter release inspection. Other fees and taxes are outside this sum.

The PDF says it took effect Aug. 10, 2026; the city fee page says Aug. 11. We label the figures “August 2026” rather than pick a date for a permit filed on that boundary.

San José's ADU FAQ also says parkland fees and school impact fees don't apply to ADUs under 750 square feet (City of San José). That school-fee statement is not the current statewide rule: the state exemption is under 500 square feet of interior livable space, not under 750. We have not verified a district-specific waiver covering the gap. Confirm the district’s rule, not just the city FAQ.

Sacramento: what does the city's own estimate show at 750 square feet?

Sacramento's own ADU fee estimate, revised July 12, 2026, shows $5,271.90 in city fees at 749 square feet and $10,624.40 at 750. Of the $5,352.50 difference, $5,347.14 comes from three impact lines the sheet starts at 750; the other listed charges add $5.36. These are the sheet’s figures, not a confirmed amount due under current law.

Here's why this table sits apart from Table 1. Since Jan. 1, 2026, state law bars impact fees on an ADU with 750 square feet of interior livable space or less. Sacramento's sheet doesn't say whether its square footage is interior livable space. Until that area basis and the applicable impact charges are resolved, do not use the 750-square-foot column as a current amount due. If your design is near 750, ask the city how it measures before you pay.

Sacramento isn't alone in drawing the line this way. San Luis Obispo County's July 7, 2026 fee guide applies its public facilities fees "to ADU ≥ 750 sf," adding $3,834 to its 750-square-foot ADU estimate of $8,796 (San Luis Obispo County-forms-and-documents/user-guides/bld-20025-07252004-user-guide-residential-permit-fee-quad-fold-pdf)). The same question remains: the guide does not identify that size as interior livable space. We reproduce the county’s example, not a confirmed fee due on a 750-interior-square-foot ADU.

Are ADUs under 750 square feet free of fees in California?

No. Since Jan. 1, 2026, California bars impact fees on an ADU with 750 square feet of interior livable space or less, but permit, plan-review and inspection fees still apply. School fees follow a separate line at 500 square feet.

Does "750 or less" include exactly 750 square feet?

Yes, for impact fees. The 2026 wording covers an ADU with "750 square feet of interior livable space or less." Some city guides still use different wording, like “less than 750” in San José’s FAQ. Sacramento’s worksheet also starts impact lines at 750 without stating that its area means interior livable space. Those sources need reconciliation, not a silent choice between them.

Watch the measuring stick, too. The state counts interior livable space. San Diego's building-fee line counts area to the outside of the walls, plus counted accessory areas. Same ADU, two different numbers, each feeding a different fee.

How much can school fees add?

Nothing for an ADU under 500 square feet of interior livable space under this exemption. For a nonexempt project, the 2026 Level 1 cap is $5.38 per square foot of assessable space. Districts adopt their own fees; Level 2 and Level 3 fees have separate rules.

Assessable space means the area within the residential structure’s perimeter, calculated by the building department, with exclusions such as garages, patios and overhangs. It is not automatically the same as interior living space. (Gov. Code §65995(b)(1))

Do cities go further than the state?

The City of San Diego does: it exempts the first two ADUs on a lot from its development impact fees at any size. San José’s under-750 parkland statement is not, by itself, broader than the state exemption through 750 square feet of interior livable space.

Other breaks have ended. San Diego County's trial ADU fee waiver ran from Jan. 9, 2019 to Jan. 9, 2024 (County of San Diego). If an article still promises it, the article is out of date.

For programs that cut or refund ADU fees now, check our ADU fee waiver tracker before you pay for plans.

What else is on the bill besides the permit?

In this Portland sample, most of it. In Portland's official sample for a new detached ADU, permit-related lines, including processing and surcharges, were $8,439.91 of a $36,720.91 total, or 23%, while system development charges and a new water service made up 74%. The sample uses July 1, 2023 rates, so read it as a picture of the mix, not a current price.

The city’s sample lists a $600 waiver-application charge as well as the full SDC lines. We kept both to reproduce its published total; this is not a bill for a project with an approved waiver. The calculation file lists every number in the 23-line permit-related group.

Think of the permit as the ticket in the door. The development charges and the water line are what it costs to plug a new home into the city.

Portland does offer a way to shrink the biggest slice. Its ADU system development charge waiver covers new ADUs that are owner-occupied or rented month-to-month or longer. The owner signs a 10-year covenant with no short-term rentals anywhere on the property, and breaking it costs 150% of the current charges (City of Portland).

Fees are one line in a much bigger budget. To see how they fit, read how much an ADU costs.

Can a modular ADU lower the permit fees?

In San José, yes, on two fees. Modular ADUs pay 10% less for plan review and 20% less for inspection, which takes $460.10 off the listed fees for a 600-square-foot ADU.

That's real money, but small next to the price of the unit itself. It isn't "20% off permits," either: the issuance fee doesn't change.

Seattle's 2026 fee table has its own line for factory-built modular construction of three stories or fewer: one base fee ($292) for the permit and one base fee per module for plan review (Seattle 2026 Fee Subtitle, Table D-2). We didn't price a Seattle modular ADU, because foundation and site work and other permits can apply. Ask Seattle's permit office how it would treat yours.

If you're weighing a factory-built unit, compare modular ADU companies on total installed cost, not the permit line.

What does each city charge beyond the two base fees?

Every schedule prints more than the two fees in Table 1. Where we could calculate named extras, we added them up: Austin reaches $1,842.04 at 600 fee-counted square feet, San Diego $17,236.32 from 501 to 3,000, San José $3,291.00 at 600, and Seattle $4,638.90 at a $150,000 value. These are still partial sums.

Austin, Texas

Austin's schedule charges $896.50 for new-construction plan review up to 1,000 square feet and $289.53 for the building permit, plus a $106.72 processing fee. It lists the trade permits separately: electrical $166.99, mechanical $116.07, plumbing $200.43 and energy $65.80. All together: $1,842.04.

From 1,001 through 2,000 square feet, plan review becomes $1,075.80 plus about 18 cents for each extra square foot, and the building fee adds under 6 cents a foot. The schedule here took effect Oct. 1, 2025 and was still the linked schedule on Sept. 29, 2026. Recheck it before using these figures on or after Oct. 1, 2026. For Texas rules beyond fees, see our Texas ADU laws guide. (Austin fee schedule; checked Sept. 29, 2026.)

Portland, Oregon

Portland's building permit for a project valued over $100,000 is $1,137.78 plus $5.63 for each extra $1,000 of value or fraction of $1,000. Standard original-submittal plan review is 65% of that. At $150,000 that's $2,341.81; at $200,000, $2,806.29.

The two-fee sum leaves out Portland’s residential development-services fee, state surcharges, trade permits and any system development charges not waived. It also assumes normal city plan review, not the separate plan-review-exempt process. (Portland fee schedule, pages 1 and 8; checked Sept. 29, 2026.)

Raleigh, North Carolina

Raleigh's new-home permit is 0.38% of the value the city calculates, up from 0.35% last fiscal year, an 8.6% rate increase. Plan review is 57% of the permit. At $150,000 that's $894.90; at $200,000, $1,193.20.

Raleigh builds its value from a February 2026 cost table, trimmed 12.4% below the national average. For a 600-square-foot home, that table gives a value well under $150,000. (Raleigh FY27 guide, residential fee and valuation tables; checked Sept. 29, 2026.)

San Diego, California

Base fees are $5,741.21 for a detached ADU up to 500 square feet and $16,487.16 from 501 to 3,000 (Table 2). Add the $737 General Plan Maintenance Fee and the $12.16 mapping fee the bulletin collects at submittal, and those become $6,490.37 and $17,236.32.

The bulletin lists more that may apply: $529.71 for each new address the city assigns, an impact-fee review charged by the hour, and water and sewer plan-check and capacity fees. If you're pricing a whole San Diego build, not just the permit, see our San Diego ADU cost guide. (San Diego IB 501, Table 501A; checked Sept. 29, 2026.)

San José, California

The listed fees are $3,291 up to 750 square feet and $5,103 from 751 to 1,200 (Table 4). Issuance includes the address; inspection includes the meter release. The hourly rule matters most on complicated projects: when review or inspection hours cost more than the table, the city charges the hours. (San José fee schedule, page 3; checked Sept. 29, 2026.)

Seattle, Washington

Seattle charges the permit and the plan review at the same amount, a "development fee index" set by project value. At $150,000 the index is $2,209, so the two fees total $4,418. A 5% technology fee brings that to $4,638.90.

For a later use of a formally established standard plan, Seattle sets review at 60% of the index. At $150,000, the permit plus that reduced review is $3,534.40 before technology fees and any hourly review of revisions. This is not the rate for every previously approved drawing. Seattle's own 500-square-foot detached-ADU example uses a $93,145 valuation and reports $3,453 in permit and review fees for 2026. Our formula gives $3,452.60 at that exact value, or $3,453 with the source’s whole-dollar display. More on local rules in our Washington ADU laws guide. (Seattle 2026 fee subtitle, Tables D-1 and D-2; checked Sept. 29, 2026.)

What changed in 2026?

Five of the six city schedules carry a 2026 effective date or edition date. California’s current ADU fee wording took effect Jan. 1, and the school-fee cap rose Jan. 28. An edition date alone does not prove every fee changed.

That's why an ADU fee number from 2024, or even early 2026, may already be stale.

Why do online ADU permit estimates disagree?

They can count different fees, use different years and measure size different ways. Portland's official $36,720.91 sample, for one, uses 2023 rates and folds in hookups and development charges, not just permits.

Here are the traps in the sources we checked:

• Base vs. total. A "permit cost" can mean two fees (like Table 1) or everything the city collects (like Portland's sample). Ask which.
• Table amounts vs. final charges. San José can charge for higher actual hours, and its Online Permits service has a separate issuance-minimum rule.
• Different measuring sticks. San Diego’s building fees use fee-counted area; California’s size exemption uses interior living space; school billing uses separately defined assessable space.
• Expired breaks. San Diego County's ADU fee waiver ended in January 2024.
• Rising schedules. Seattle's sample detached-ADU fee rose 18.7% in a single year.

What should you check before you pick a design?

Ask the city these questions before you lock a floor plan: how it measures your ADU's size for fees, what value it will assign the project, and which other agencies will send you a bill.

1. Get the fee area in writing. In San Diego, 500 versus 501 square feet is a $10,745.95 difference in base fees.
2. Know your interior livable space. In California, 750 or less means no impact fees, and under 500 means no school fee.
3. Ask about attached vs. detached. In San Diego, a 600-square-foot attached ADU's base fees are $9,601.95 lower than a detached one.
4. Ask for a line-item estimate. Include water and sewer, school district and any impact fees, not only the building permit.
5. Check the schedule date. Five of the six schedules have a 2026 edition or effective date.

If you're still working out what your lot allows, The Dwelling Index's free property eligibility check is a quick place to start. Treat it as a planning aid, not city approval.

How we built this

We read the current official fee schedules for six cities: Austin (effective Oct. 1, 2025), Portland (July 10, 2026), Raleigh (FY27, from July 1, 2026), San Diego (August 2026 edition), San José (August 2026) and Seattle (2026). We chose them because each publishes an ADU or new-house fee rule we could apply to a single, stated input.

For cities that charge by size, we used 600 square feet, plus sizes on either side of each size line (500 and 501 in San Diego; 750 and 751 in San José). For cities that charge by value, we used $150,000 and $200,000 as stand-in values. Every formula is in the dataset, row by row.

We used decimal arithmetic and rounded each computed fee to the cent. Seattle allows whole-dollar rounding of assessed fees, with .50 rounded down; the worksheet keeps cents. As a check, our Seattle formula reproduces the city's own 2026 sample detached-ADU fee of $3,453.

Supporting figures (Sacramento's and San Luis Obispo County's estimates, Portland's 2023 sample, Seattle's sample fee, Riverside County's deposit, and California's rules) are taken as the agencies printed them. Where we grouped or divided those numbers, we say so.

The rate inputs were read from the government documents for this Sept. 29, 2026 audit, and every published scenario was recalculated. For San José’s PDF we reused the primary-source extraction and page check obtained earlier the same day and rechecked the linked city fee page; its date conflict is shown above. We did not obtain project-specific fee determinations from any agency. Our editorial standards are on the methodology page.

What this data does and doesn't show

It shows base permit fees from each city's current schedule for stated inputs, the exact size steps in San Diego and San José, and California's 2026 fee lines. It shows selected charges each schedule prints beyond the two base fees.

It doesn't show a final bill. It isn't a like-for-like ranking, since cities use different inputs and bundle different work into their fees. It doesn't cover impact, school or utility charges for most of the six cities. It covers six cities, not every city. And San Diego's attached-ADU figures rely on our reading of the table's base-plus-increment columns.

How to cite this page

The Dwelling Index. "ADU Permit Fees by City: 6 Cities Itemized (2026)." Dwelling Index Research, updated September 2026. Sources checked Sept. 29, 2026. https://dwellingindex.com/research/adu-permit-fees/

To point to one finding, use its anchor: #san-diego-500-501, #san-jose-750-751, #california-750 or #portland-2023-sample.

You may reuse the original calculations, table arrangement and chart design we own with credit to The Dwelling Index. Keep underlying source attribution and any source license terms; this permission does not license third-party material or require a link.

Download the data

Three free CSV files, no sign-up: 24 calculated fee scenarios, 29 fee rules and official examples, and 46 calculation checks, including the school-cap examples and Portland’s 23-line group. Every row carries its formula or wording, source link and check date. A blank cell means “not calculated,” not zero. Each sum covers only its named components.

ADU permit fee questions

How much does it cost to get an ADU permit in San Diego?

$5,741.21 in base plan-check and inspection fees for a detached ADU up to 500 fee-counted square feet, and $16,487.16 from 501 to 3,000, under the city’s August 2026 schedule. Fee area includes the outside walls and counted accessory areas. The bulletin's $749.16 in submittal fees brings those to $6,490.37 and $17,236.32. Other charges are not included; water, sewer and school charges depend on the project and applicable exemptions. The city exempts the first two ADUs on a lot from its development impact fees. (San Diego fee schedule; city DIF rule; checked Sept. 29, 2026.)

How much are ADU permit fees in California?

There's no statewide price. San José's listed ADU fees are $3,291 up to 750 square feet and $5,103 from 751 to 1,200; San Diego's base fees are $5,741.21 or $16,487.16 depending on size. State law bars impact fees on ADUs with 750 square feet of interior livable space or less, but permit and inspection fees still apply. (San José schedule; San Diego schedule; state rule; checked Sept. 29, 2026.)

How much are permit fees for a 600-square-foot ADU?

In our comparison, base building and review fees for a detached ADU with 600 fee-counted square feet are $1,186.03 in Austin, $2,869.00 in San José and $16,487.16 in San Diego. Portland, Raleigh and Seattle charge by project value instead, so size alone doesn't set their fee. (Austin schedule; San José schedule; San Diego schedule; checked Sept. 29, 2026.)

Does California's fee exemption include exactly 750 square feet?

Yes, for impact fees. Since Jan. 1, 2026, ADUs with 750 square feet of interior livable space or less owe none. The break doesn't cover permit, plan-review or inspection fees, and school fees use a separate 500-square-foot line. (state exemption; checked Sept. 29, 2026.)

Do ADUs pay school fees in California?

An ADU under 500 square feet of interior livable space meets the state exemption. For a nonexempt project, the 2026 Level 1 cap is $5.38 per assessable square foot: $4,035 at 750 assessable square feet, before credits. Assessable space is not automatically interior living space; confirm the district’s adopted rate and fee level. (state exemption; assessable space; 2026 Level 1 cap; checked Sept. 29, 2026.)

Is San Diego County still waiving ADU fees?

No. The county's trial ADU fee waiver ran from Jan. 9, 2019 to Jan. 9, 2024. The City of San Diego, a separate government, exempts the first two ADUs on a lot from its development impact fees. (county program end; city DIF rule; checked Sept. 29, 2026.)

Will the lookup tell me exactly what I'll pay?

No. It shows base fees from each city's schedule for the size or value you enter, plus what that schedule leaves out. For your real number, ask the city and every other agency that bills the project for a line-item estimate.

Sources

1. City of San Diego, Information Bulletin 501: Fee Schedule for Construction Permits-Structures, August 2026 edition, Table 501A and footnotes 5-6, Sections II, III, V, VII. Checked Sept. 29, 2026.
2. City of San José, FY 2026-27 Building Division Fee Schedule, August 2026 schedule, ADU New/Alteration table and footnotes. Checked Sept. 29, 2026.
3. City of Austin, Residential Building Plan Review & Inspection Permit Fees, effective Oct. 1, 2025, sections labeled 1 and 5 of 6 (PDF pages 1 and 6). Checked Sept. 29, 2026.
4. City of Portland, Building and Other Permits Fee Schedule, effective July 10, 2026, building permit fee table and plan review rate. Checked Sept. 29, 2026.
5. City of Raleigh, Development Fee Guide, July 1, 2026 - June 30, 2027, Permit Fees for New Residential Construction and Building Valuation Data. Checked Sept. 29, 2026.
6. City of Seattle SDCI, 2026 Fee Subtitle, Tables D-1 and D-2, sections 22.900A.040 and 22.900A.100. Checked Sept. 29, 2026.
7. City of Seattle SDCI, 2026 Fee Changes, example projects. Checked Sept. 29, 2026.
8. City of Portland, New Single Family Residence (NSFR) and New Detached ADU Sample Fees, rates effective July 1, 2023. Checked Sept. 29, 2026.
9. City of Portland, Apply for an ADU System Development Charge Waiver. Checked Sept. 29, 2026.
10. California Government Code §66311.5 (renumbered from §66324 by SB 543, Stats. 2025, ch. 520), effective Jan. 1, 2026. Checked Sept. 29, 2026.
11. California Government Code §66323, subdivision (a)(1). Checked Sept. 29, 2026.
12. State Allocation Board, Index Adjustment on the Assessment for Development, Jan. 28, 2026. Checked Sept. 29, 2026.
13. City of Sacramento, Accessory Dwelling Unit (ADU) Fee Estimate (New Construction), CDD-0419, revised July 12, 2026. Checked Sept. 29, 2026.
14. San Luis Obispo County, A User's Guide to Residential Permit Fees (BLD-2005)-forms-and-documents/user-guides/bld-20025-07252004-user-guide-residential-permit-fee-quad-fold-pdf), revised July 7, 2026. Checked Sept. 29, 2026.
15. City of San Diego, Public Spaces Frequently Asked Questions (development impact fees and ADUs, SDMC §142.0640(b)(1)). Checked Sept. 29, 2026.
16. County of San Diego Planning & Development Services, ADU Information. Checked Sept. 29, 2026.
17. City of San José, ADU FAQs. Checked Sept. 29, 2026.
18. Riverside County TLMA Building and Safety, Building and Safety Fee Schedules. Checked Sept. 29, 2026.
19. California Government Code §65995(b)(1), definition and calculation of residential assessable space for school fees. Checked Sept. 29, 2026.
20. California Education Code §17620, school development-fee authority and assessable-space context. Checked Sept. 29, 2026.
21. City of San José, Building Permit Fees, linked fee schedule and Aug. 11, 2026 date statement. Checked Sept. 29, 2026.

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