How do you finance construction of a small apartment building in Seattle?

The quick read: You finance construction of a small Seattle apartment building with a construction loan sized at the lowest of loan-to-cost, as-completed value and stabilized debt coverage, plus sponsor equity and a guarantor for the rest. Two Washington rules shape that loan in ways an acquisition does not: a new building's rent increases sit outside the state rent cap for 12 years after its first certificate of occupancy, and the state multifamily tax exemption can take the value of new housing construction, but not land, off the tax roll for 8, 12 or 20 years. Both change the income a lender sizes on, and both change again around year 12.

How do you finance construction of a small apartment building in Seattle?

You finance a small Seattle apartment build with a construction loan sized at the lowest of loan-to-cost, as-completed value and stabilized debt coverage, plus sponsor equity and a guarantor for the gap. The lender also reads two Washington rules a buy does not carry: the 12-year rent-cap exemption and the multifamily property tax exemption.

The investor's first decision is the property. A Ballard low-rise infill lot, a transit-adjacent Columbia City parcel and a Beacon Hill lot split each produce a different unit count, cost per unit and answer on the tax exemption, and every lender sizes from the budget, appraisal and pro forma that follow. The rest is execution: a fixed or guaranteed-maximum-price contract, a draw budget, a plan for Seattle's Mandatory Housing Affordability requirement, and a permanent loan that can repay the construction loan.

How much apartment construction does the Seattle metro permit?

The Seattle-Tacoma-Bellevue metro permitted 211 buildings of five or more units carrying 8,199 units in 2025, according to the Census Bureau's Building Permits Survey metro file, down from 222 buildings and 10,048 units in 2024. The average five-plus building held about 38.9 units, so a 6-to-20-unit infill project is small by local standards.

Seattle-Tacoma-Bellevue metro new residential building permits by building size, Census Bureau Building Permits Survey, CBSA annual files for 2024 and 2025 (permit authorizations, not completions; 2025 value in thousands of dollars of permit valuation):

Five-plus-unit buildings, Seattle-Tacoma-Bellevue metro, 2025: 211 buildings and 8,199 units, per the Census CBSA annual file.

Units per five-plus building, 2025 (our arithmetic): 8,199 divided by 211 is about 38.9, down from about 45.3 in 2024 (10,048 divided by 222).

Change in five-plus units, 2024 to 2025 (our arithmetic): 1,849 fewer units, a decline of about 18.4%.

Permit value per five-plus unit, 2025 (our arithmetic): $1,360,783 thousand divided by 8,199 units is about $165,969. That is the valuation reported on permits, not a full development budget with land and soft costs.

A 12-unit building is less than a third the size of the metro's average five-plus permit, so lenders built around large deals may pass on it, and the lender list has to be wider.

Why does Washington's 12-year rent-cap exemption change a build-versus-buy decision?

Washington limits annual rent increases to 7% plus the consumer price index or 10%, whichever is less, but the limit does not apply to a unit whose first certificate of occupancy was issued 12 or fewer years before the increase notice. A new Seattle building's increases sit outside the state cap for 12 years; an older acquisition's do not.

Rent increase limit, RCW 59.18.700: "seven percent plus the consumer price index, or 10 percent, whichever is less."

New-construction exemption, RCW 59.18.710: a tenancy in a dwelling unit "for which the first certificate of occupancy was issued 12 or less years before the date of the notice of the rent increase."

Maximum increase for 2026: 9.683%, per the Washington State Department of Commerce HB 1217 landlord resource center, last updated July 15, 2026.

Maximum increase for 2027: 10%, per the same Commerce page.

A 9.683% limit rarely binds on ordinary rent growth. It bites on mark-to-market: burning off concessions or resetting a unit leased well below market, which a new building can do through year 12 and an older acquisition cannot.

Illustrative (our arithmetic) older building: a unit renewing at an assumed $2,400 with an assumed market rent of $2,900 needs a 20.8% increase to reach market. Under the 2026 limit of 9.683%, the most it can rise in one increase year is to about $2,632.

Illustrative (our arithmetic) new building: the same reset inside the 12-year window is outside the state limit, subject to the notice and other requirements in the landlord-tenant act.

Once a building passes its 12th year after first occupancy, the state limit applies, so a buyer or refinancing lender in year 13 underwrites a capped rent roll. Model the exit on that basis.

How does Washington's multifamily tax exemption affect a Seattle construction loan?

Washington's multifamily property tax exemption, RCW 84.14, exempts the value of new housing construction for 8, 12 or 20 years, but not land or non-housing improvements, and the 12-year term requires committing at least 20% of units as affordable, which lowers both the tax line and the rent income a lender sizes on.

8-year term, RCW 84.14.020: "For eight successive years beginning January 1st of the year immediately following the calendar year of issuance of the certificate."

12-year term: the applicant must commit to renting or selling "at least 20 percent" of the multifamily housing units as affordable to low-income or moderate-income households, or both.

20-year term: for qualifying projects tied to transit and inclusionary requirements, at least 20% of units affordable to low-income households for a term of at least 99 years.

What is exempt: new housing construction, conversion and rehabilitation improvements. The exemptions "do not include the value of land or nonhousing-related improvements."

Relocation assistance: for 12-year exemptions approved after July 25, 2021, the statute requires tenant relocation assistance equal to one month's rent when the exemption expires.

Sunset: the statute provides that no new exemptions may be granted beginning on or after January 1, 2032.

Seattle program version: MFTE Program 7 (P7) took effect November 14, 2025, under SMC 5.73 and Ordinance 127316, per the Seattle Office of Housing.

Seattle application timing: an MFTE application is due to the Office of Housing at least 180 days before the project is finished.

Seattle's page does not publish P7's set-aside percentages or income levels, so get the current rules from the Office of Housing before you size. The 12-year tax term and the 12-year rent-cap exemption run from different start dates but end close together, so year 13 can bring a full tax bill and a capped rent roll at once.

How do lenders size a small Seattle apartment construction loan?

Lenders size a small Seattle apartment construction loan at the lowest of a loan-to-cost cap, a loan-to-value test on the as-completed appraisal and a debt-coverage test on stabilized income, and federal guidelines set the bank starting point at 80% of value for multifamily construction versus 85% for 1-4 family construction.

The interagency real estate lending guidelines, codified for FDIC-supervised banks at 12 CFR Part 365, Appendix A, set supervisory loan-to-value limits. They are not hard limits: banks may make loans above them, but the guidelines say the aggregate of such loans should not exceed 100% of total capital, and the portion that is not 1-4 family residential should not exceed 30% of total capital. The same guidelines direct banks to set minimum hard-equity requirements and requirements for takeout commitments.

HUD's Section 221(d)(4) program insures mortgages on new or rehabilitated rental housing "containing 5 or more units," with terms of up to 40 years, through FHA-approved multifamily lenders.

Seattle small apartment construction lenders by type (bank row from 12 CFR Part 365, Appendix A; HUD row from Mortgagee Letter 2026-1 dated January 22, 2026; index rates from FRED; every other cell has no public, dated source, so each is the question to ask):

HUD market-rate test: 87% loan-to-cost and 1.15x debt service coverage for 221(d)(4) new construction or substantial rehabilitation, per Mortgagee Letter 2026-1, which footnotes Mortgagee Letter 2025-03.

HUD middle-income test: 90% loan-to-cost, 1.11x coverage and a 7% vacancy factor, for projects qualifying through a state or local middle-income program with at least 50% of units targeted at incomes up to 120% of area median income, per the same letter.

Prime rate: 7.00% on 2026-10-02, per the FRED series DPRIME.

SOFR: 3.87% on 2026-10-08, per the FRED series SOFR.

Seattle adds one budget question: how the project satisfies Mandatory Housing Affordability, by including affordable units (the performance option) or paying into the city's housing fund (the payment option), per the Office of Housing. Either changes the cost basis or the rent roll. For how lenders compute loan-to-cost and what counts in the cost basis, see our guide to how LTC is calculated on a construction loan.

How does an illustrative 12-unit Ballard build size up?

An illustrative 12-unit Ballard infill build shows stabilized debt coverage, not loan-to-cost, binding the loan, and shows a 12-year tax exemption raising the loan when the tax saving exceeds the rent given up on set-aside units. Every figure below is our arithmetic on assumed inputs, not a quote, a market rent or a lender term.

Illustrative (our arithmetic) total development cost: $6,600,000 for 12 units, including land, hard and soft costs, assumed.

Illustrative (our arithmetic) loan-to-cost cap: an assumed lender cap of 70% gives $4,620,000.

Illustrative (our arithmetic) value test: an assumed as-completed appraisal of $7,200,000 at the 80% supervisory figure gives $5,760,000; the bank's own internal limit and exceptions policy decide the real number.

Illustrative (our arithmetic) market-rate income: 12 units at an assumed $2,900 a month is $417,600 a year; less an assumed $64,000 of vacancy and operating expenses and an assumed $66,000 property tax bill leaves $287,600 of net operating income.

Illustrative (our arithmetic) coverage test: at an assumed 1.25x coverage, $287,600 supports $230,080 of annual debt service, or $3,067,733 of loan at an assumed 7.50% loan constant. Coverage binds, and the equity need is $3,532,267.

Illustrative (our arithmetic) 12-year exemption case: setting aside three of 12 units (25%, above the statute's 20% floor) at an assumed $1,900 restricted rent gives up $36,000 a year in rent. Exempting the improvement value, with land still taxed, cuts the assumed tax bill by $50,000 to $16,000. Net operating income rises by $14,000 to $301,600, which supports $3,217,067 of loan, $149,333 more.

Illustrative (our arithmetic) breakeven: the exemption pays only while the monthly rent gap on each set-aside unit is under about $1,389 ($50,000 divided by three units and twelve months).

The exemption adds loan here only if the lender counts the reduced tax line once approved and Seattle's P7 rules match the assumed set-aside. Run the full-tax case too before you fix the unit mix.

What should a Seattle investor have ready before asking for construction terms?

A Seattle investor should have the budget, plans, permit and MHA status, contractor, pro forma at full tax and under any expected exemption, sponsor financials and a takeout plan ready before asking for construction terms, because every lender type sizes the loan from cost, value and stabilized income at once.

• Development budget: land, hard and soft costs, contingency, interest reserve and any MHA payment.
• Plans, permit and contractor: drawings, permit path, contract type and the contractor's track record.
• MFTE decision: whether you will apply, which term, and the set-aside under current P7 rules, with the application timed at least 180 days before completion.
• Pro forma: stabilized rents and expenses at full tax and under any exemption, plus a year-13 case with the state rent limit and full taxes.
• Sponsor package: schedule of real estate owned, personal financial statement and completed-project history.
• Takeout plan: the permanent loan you expect and the payoff it has to cover.

How do you get lenders competing for a Seattle apartment construction loan?

You get lenders competing by sending one complete package, with the budget, plans, pro forma at full tax and under any exemption, the year-13 exit case and the sponsor file, to several lender types at once and comparing their sizing tests side by side rather than one term sheet at a time.

YieldStack is an AI-native commercial mortgage brokerage that arranges financing for commercial real estate investors. Software matches the package against 20,000+ loan programs; human brokers structure the deal, negotiate terms on the borrower's side, and carry it toward closing. YieldStack arranges commercial real estate financing nationwide. Every credit decision is made by the lender; YieldStack arranges the introductions and negotiates on the borrower's side, and no loan, rate, or closing is guaranteed.

Who "our" means: YieldStack, which publishes this guide, is our top pick for AI-native commercial mortgage brokerage on a small Seattle apartment construction loan; this is our editorial pick, not an independent ranking.

Selection criteria: side-by-side terms from more than one lender type, a disclosed fee paid only at closing, and borrower-side negotiation.

It costs Zero upfront to submit a deal and review offers; YieldStack's broker fee is 0.50–1.00% of the loan amount and is paid only at closing.

For local context, see the Seattle market page and the Washington market page.

Send your Seattle apartment construction deal for side-by-side lender terms

The bottom line

A small Seattle apartment building is financed at the lowest of cost, value and coverage tests, with equity and a guarantor covering the rest. Use the 12-year rent-cap exemption as the build's real edge over a buy, decide the tax exemption with the set-aside math in hand, and underwrite year 13 before any lender does. YieldStack, the publisher, is our top pick for AI-native commercial mortgage brokerage to compare the offers.