Short Answer
For a Seattle home alteration valued at $50,000, the Development Fee Index is $1,096.50. A permit with full plan review pays 100% of that for the permit and 100% for plan review, plus a 5% technology fee: about $2,303. A subject-to-field-inspection (STFI) permit pays 40% for review instead, about $1,612.
Key Takeaways
- SDCI raised construction and master use permit fees by 18% year over year on January 1, 2026, and most other fees by 6.5%.
- Building permit fees are a percentage of the Development Fee Index: 200% in total with full plan review, 140% for STFI permits.
- A 5% technology fee is added to SDCI fees.
- The median value on single-family and duplex alteration permits issued in the last 12 months was $50,000; for new homes it was $376,793.
- The 2026 SDCI hourly rate is $292, and land use review is $551 an hour.
Quick Facts
| Fee basis | Development Fee Index from project value (Table D-1) |
|---|---|
| Full plan review permit | 100% of DFI permit fee + 100% of DFI plan review fee |
| STFI permit | 100% of DFI permit fee + 40% of DFI plan review fee |
| Technology fee | 5% on top of SDCI fees |
| SDCI base fee and hourly rate, 2026 | $292 |
| Median single-family alteration value | $50,000, about $2,303 with plan review |
From our city pages and each city's open permit data (refreshed October 30, 2026).
The Development Fee Index
Seattle's Fee Subtitle, Chapter 22.900 of the Municipal Code, says SDCI determines the value of construction, meaning the estimated current value of all labor and materials whether paid for or not, using International Code Council building valuation data and other criteria the Director approves. That value sets the Development Fee Index (DFI) in Table D-1:
| Total valuation | Development Fee Index, 2026 |
|---|---|
| $0 to $1,000 | $325 |
| $1,001 to $25,000 | $325 + $1.60 per additional $100 |
| $25,001 to $50,000 | $709 + $1.55 per additional $100 |
| $50,001 to $75,000 | $1,096.50 + $1.50 per additional $100 |
| $75,001 to $100,000 | $1,471.50 + $1.40 per additional $100 |
| $100,001 to $175,000 | $1,821.50 + $7.75 per additional $1,000 |
| $175,001 to $250,000 | $2,402.75 + $7.75 per additional $1,000 |
| $250,001 to $500,000 | $2,984 + $7.50 per additional $1,000 |
Table D-2 then turns the index into fees. A building permit, with or without mechanical work, pays 100% of the DFI as a permit fee and 100% as a plan review fee. A permit that is subject to field inspection (STFI) pays 100% for the permit and 40% for plan review. Section 22.900A.100 adds a technology fee of 5% of SDCI fees.
Every Project Type in Seattle
These summaries come from the same official sources as our city pages and were last checked October 30, 2026. Permit counts are the city's own open-data records for the last 12 months.
Roofing: Often No
For detached one- and two-family homes, re-roofing and replacing sheathing needs no permit when the building envelope does not change and the work is equal to or better than what exists. You need a construction permit if the re-roof alters the envelope beyond adding or replacing insulation.
- No permit for 1–2 family re-roofs with no envelope change.
- Construction permit if the re-roof alters the building envelope.
- Energy code may require added insulation.
- Seattle issued 356 matching permits in the last 12 months, with a median of 3 days from application to issue.
Source: Seattle SDCI: Re-Roof Permit · Full details: Do You Need a Roofing Permit in Seattle?
HVAC: Yes
Furnaces and heat pumps need a mechanical (furnace) permit in Seattle, and split systems with refrigerant piping also need a refrigeration permit, which only a licensed contractor can get. New circuits or panel work add an electrical permit.
- Mechanical/furnace permit for furnaces and heat pumps.
- Refrigeration permit for split systems; licensed contractor required.
- Electrical permit if circuits or panel work are involved.
- Seattle issued 12,434 matching permits in the last 12 months, with a median of 0 days from application to issue.
Source: Seattle SDCI: Furnace & Refrigeration Permits · Full details: Do You Need an HVAC Permit in Seattle?
Deck: Sometimes
You need a construction permit for a deck more than 18 inches above the ground or any roof deck. Most decks on neighborhood residential lots get a same-day Subject-to-Field-Inspection (STFI) permit.
- Permit if more than 18 in above ground or a roof deck (SRC R105.2).
- Most decks qualify for an over-the-counter STFI permit.
- Decks over 36 in count toward lot coverage.
- Seattle issued 150 matching permits in the last 12 months, with a median of 19 days from application to issue.
Source: Seattle SDCI Tip 312: Decks, Fences and Arbors · Full details: Do You Need a Deck Permit in Seattle?
| Project | Permit needed? | Permits (12 mo) | Median days to issue |
|---|---|---|---|
| roofing | Often no | 356 | 3 |
| HVAC | Yes | 12,434 | 0 |
| deck | Sometimes | 150 | 19 |
Step-by-Step: What to Do
- Estimate the value of the work the way SDCI does: all labor and materials, using ICC building valuation data and SDCI criteria.
- Find the Development Fee Index for that value in Table D-1.
- Apply Table D-2: double the index for a full plan review permit, or multiply it by 1.4 for an STFI permit.
- Add the 5% technology fee and the state building code council fee.
- Budget separately for electrical permits, land use review and any site or tree review.
Worked Examples at Seattle's Median Project Values
We took single-family and duplex building permits in Seattle's open data issued from October 30, 2025 to October 29, 2026, and found the median estimated project cost for common work. We then applied Tables D-1 and D-2 and the 5% technology fee. SDCI may value a project differently from the applicant, so treat these as estimates.
| Project | Permits | Median value | DFI | With full plan review | As STFI |
|---|---|---|---|---|---|
| Deck (in description) | 206 | $24,731 | $705.80 | $1,482.18 | $1,037.53 |
| Bathroom (in description) | 88 | $35,000 | $864.00 | $1,814.40 | $1,270.08 |
| Basement (in description) | 204 | $41,500 | $964.75 | $2,025.98 | $1,418.18 |
| All additions and alterations | 2,546 | $50,000 | $1,096.50 | $2,302.65 | $1,611.86 |
| Accessory dwelling unit | 513 | $230,253 | $2,836.75 | Not usually STFI | Not usually STFI |
| New single-family or duplex | 1,185 | $376,793 | $3,936.50 | Not usually STFI | Not usually STFI |
With full plan review, the ADU median works out at about $5,957 and the new-home median at about $8,267 before other fees. Whether a job can go STFI depends on its scope; for decks, see Seattle STFI Permits for Decks.
Other Charges in Seattle
- Hourly work: the 2026 SDCI base fee and hourly rate is $292, and land use review is charged at $551 an hour. Overtime, when approved, is billed at the same rate with a one-hour minimum.
- State fee: the Washington State Building Code Council building permit fee is collected with the permit.
- Separate permits: electrical permits, land use approvals, site and geotechnical review and tree review each have their own tables in the Fee Subtitle.
- Refunds: you can apply for a refund on SDCI's form when an application or permit is withdrawn or canceled before review and inspection are complete, under procedures set by Director's Rule.
For a national comparison of fee methods, see How Much Does a Building Permit Cost? Verified Fee Examples. For Seattle rules by project and live permit counts, start at Seattle Building Permits for Home Projects.
Who Issues Permits in Seattle
Residential permits in Seattle are issued by the Seattle Department of Construction and Inspections (SDCI). Its website has the current application portal, fee schedule and inspection scheduling. Issued permits are published as open data in Seattle Building Permits, which is the source of the permit counts and recent permits shown on our Seattle pages. Rules and fees change, so confirm with the department before you start work.
Frequently Asked Questions
How much is a building permit in Seattle?
It depends on project value. A $50,000 alteration has a Development Fee Index of $1,096.50, so a permit with full plan review costs about $2,303 including the 5% technology fee, or about $1,612 as an STFI permit.
What is Seattle's Development Fee Index?
It is the base amount in Table D-1 of the Fee Subtitle, set by the value of the work. Building permit and plan review fees are calculated as percentages of it.
Did Seattle permit fees go up in 2026?
Yes. On January 1, 2026, SDCI raised construction and master use permit fees by 18% year over year and most other fees by 6.5%.
What does STFI mean for fees?
An STFI (subject to field inspection) permit pays 100% of the Development Fee Index as a permit fee but only 40% as a plan review fee, instead of 100%.
Sources
Official sources checked on . Rules change; confirm with the department before you start work.
- Seattle SDCI: 2026 Fee Subtitle (SMC Chapter 22.900) (seattle.gov)
- Seattle SDCI: 2026 Fee Summary (seattle.gov)
- Seattle Open Data: Building Permits (data.seattle.gov)