Data Sources & Methodology

QuickBuildCost 2026 rates and finish levels

Until NAHB publishes its next survey, the calculator also offers QuickBuildCost 2026 rates: each of the 36 NAHB 2024 cost lines updated from late 2024 to September 2026 with the matching Bureau of Labor Statistics producer price index, plus construction wages. At standard finishes this comes to about $174.52 per sq ft. The finish level (basic, standard, premium, luxury) adjusts nine finish-sensitive lines using published installed-cost tiers. The method, every index and every source are on our 2026 cost research page.

Key terms explained

Several industry abbreviations and data sources are referenced throughout this site. Here is what each one means:

NAHB: National Association of Home Builders

The National Association of Home Builders (NAHB) is the largest US trade association representing the residential construction industry, with more than 140,000 member firms including home builders, remodelers, and associated professionals. NAHB publishes annual research on construction costs, housing starts, and builder sentiment that is widely used as the industry benchmark. The primary data source for this site is the NAHB 2024 Cost of Constructing a Home survey.

NAHB/Wells Fargo HMI: Housing Market Index

The NAHB/Wells Fargo Housing Market Index (HMI) is a monthly survey of NAHB members that gauges builder confidence in the market for newly built single-family homes. it is scored on a scale of 0-100, where any reading above 50 indicates that more builders view conditions as good than poor. The HMI is also used to track material cost trends and supply chain conditions, which is why it is referenced on this site for building material cost inflation data.

NAIC: National Association of Insurance Commissioners

The National Association of Insurance Commissioners (NAIC) is the US standard-setting and regulatory support organisation for state insurance regulators. NAIC publishes an annual homeowners insurance report with average premiums by state. The mortgage calculator's homeowners insurance defaults come from the edition covering 2023 data (published July 2026).

Tax Foundation

The Tax Foundation is an independent non-partisan tax policy research organisation based in Washington, DC. It publishes annual analyses of state and local tax burdens, including effective property tax rates by state, calculated from US Census Bureau American Community Survey data. The mortgage calculator's property tax defaults come from its Facts & Figures 2026 report.

PMMS: Freddie Mac Primary Mortgage Market Survey

The Freddie Mac Primary Mortgage Market Survey (PMMS) publishes national average rates for 30-year and 15-year fixed-rate mortgages every week. The mortgage calculator uses these as its default interest rates. PMMS does not publish averages for other terms, so for 20-year and 10-year loans the calculator asks you to enter your own rate.

PMI: Private Mortgage Insurance

Private Mortgage Insurance (PMI) is insurance that a lender may require a borrower to purchase when the down payment on a home is less than 20% of the purchase price. PMI protects the lender (not the borrower) if the borrower defaults on the loan. The cost varies by lender, credit score and down payment, so the mortgage calculator asks you to enter the PMI rate from your lender's quote. PMI can usually be cancelled once the borrower reaches 20% equity in the home.

ARM: Adjustable-Rate Mortgage

An Adjustable-Rate Mortgage (ARM) is a home loan with an interest rate that changes periodically based on a benchmark index (such as the Secured Overnight Financing Rate, SOFR). ARMs typically start with a fixed rate for an initial period (e.g. 5 years in a 5/1 ARM), then adjust annually. They can offer lower initial rates than fixed-rate mortgages but carry the risk of payment increases if rates rise.

LTV: Loan-to-Value Ratio

Loan-to-Value (LTV) ratio is the percentage of a property's value that is financed by a mortgage. It is calculated as (loan amount ÷ property value) × 100. A lower LTV means more equity and less risk for the lender. Most conventional lenders require an LTV of 80% or below to avoid PMI. LTV also affects the interest rate offered: lower LTV typically means a better rate.

Primary data source: NAHB 2024 Cost of Constructing a Home

All construction cost figures, stage shares, and sub-category shares in the calculator are derived from the NAHB 2024 Cost of Constructing a Home survey, published by the National Association of Home Builders. Key figures from that survey used on this site:

• Average construction cost: $428,215
• Average cost per square foot: approximately $162
• Average finished area: 2,647 sq ft
• Construction as % of average sales price: 64.4%
• Finished lot as % of average sales price: 13.7%
• Builder profit as % of average sales price: 11.0%
• Builder overhead as % of average sales price: 5.7%
• Overhead plus profit as a markup on construction cost: ($38,248 + $72,971) ÷ $428,215 ≈ 26%. This is the figure the calculator suggests for the builder overhead & profit field, because the field is applied to construction cost, not to the sales price.
• Stage and sub-category shares of total construction cost (see table below)

Material cost trend data

Building material costs rose 6.7% over the 12 months to July 2026, according to the NAHB/Wells Fargo Housing Market Index (July 2026). This figure is cited on this site to note that costs may have changed since the 2024 survey data was collected.

Mortgage calculator data

The mortgage calculator fills in these defaults. You can override any of them with your own figures. All were last checked on October 18, 2026.

• Interest rate, 30-year fixed: the average of the published 30-year fixed rates from the five lenders listed for your state (see lender rates by state below).
• Interest rate, fallback and 15-year fixed: Freddie Mac PMMS national averages for the week of October 15, 2026: 7.40% for a 30-year fixed and 6.71% for a 15-year fixed (source). There is no default for 20-year or 10-year loans.
• Property tax: mean effective property tax rate on owner-occupied housing (taxes paid ÷ home value) by state for calendar year 2024. Taken from Table 33 of the Tax Foundation's Facts & Figures 2026, which is calculated from US Census Bureau American Community Survey data. Rates within a state vary a lot by county.
• Homeowners insurance: average annual premium for the HO-3 policy form (the most common homeowners policy) by state, 2023 data. Taken from Table 4 (“Total” row) of the NAIC Homeowners Insurance Report: Data for 2023, published July 2026. Premiums have changed since 2023, and the NAIC notes that differences in state coverage rules make state-by-state comparisons difficult.
• PMI: no default. Enter the rate from your lender's Loan Estimate.

Lender rates by state

The mortgage calculator lists five lenders for each state with the 30-year fixed rate, APR and discount points each one advertises, and uses the average of those rates as the state's default 30-year rate. Every figure was read from the lender's own rates page on October 18, 2026. We took the first 30-year fixed purchase rate shown on each page and recorded the date the page gives for it. We did not estimate any rate. If a lender does not publish its rate online, we either chose another lender that does or list it as “not published”.

Each state shows up to three local credit unions or banks first, then national lenders that publish a separate rate for each state, then national credit unions that publish one rate for every state and require membership. Per-state national lenders appear only in states where their own licensing page lists a license: Lower is not listed in Hawaii, New York or Vermont, and Total Mortgage is not listed in Alaska, Colorado, Hawaii, Idaho, Missouri or Wisconsin. These are advertised “as low as” rates for each lender's example borrower, with different points, so they are a starting point and not a quote.

Lenders and source pages

• 1st Nor Cal Credit Union (CA): rates page
• AllSouth Federal Credit Union (SC): rates page
• America First Credit Union (UT): rates page
• Avadian Credit Union (AL): rates page
• BayPort Credit Union (VA): rates page
• Bellwether Community Credit Union (NH): rates page
• Blaze Credit Union (MN): rates page
• Charter Oak Federal Credit Union (CT): rates page
• Chase (IL): rates page
• Communication Federal Credit Union (OK): rates page
• Community First Credit Union (WI): rates page
• Credit Union 1 (AK): rates page
• Desert Financial Credit Union (AZ): rates page
• Eastrise Federal Credit Union (VT): rates page
• Educators Credit Union (WI): rates page
• Ent Credit Union (CO): rates page
• Fidelity Bank (KS): rates page
• Goldenwest Credit Union (UT): rates page
• Greater Iowa Credit Union (IA): rates page
• Hawaii State Federal Credit Union (HI): rates page
• Honor Credit Union (MI): rates page
• Lighthouse Credit Union (CT, FL, ME, MA, NH, RI, VT): rates page
• Lower (AL, AK, AZ, AR, CA, CO, CT, DE, FL, GA, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, WA, WV, WI, WY): one rates page per state, for example lower.com/mortgages/mortgage-rates/alabama
• Municipal Credit Union (NY): rates page
• Navy Federal Credit Union (AL, AK, AZ, AR, CO, DE, GA, HI, ID, IL, IN, IA, KS, KY, LA, ME, MD, MS, MO, MT, NE, NV, NJ, NM, NY, NC, ND, OH, OR, PA, SD, TN, TX, WA, WV, WI, WY): rates page
• OnPoint Community Credit Union (OR): rates page
• Pearl Hawaii Federal Credit Union (HI): rates page
• PenFed Credit Union (AK, AR, CO, DE, GA, ID, IN, KY, LA, MS, MO, MT, NE, NV, NJ, NC, ND, OH, PA, SD, TN, WA, WV, WY): rates page
• Rio Grande Credit Union (NM): rates page
• Sacramento Credit Union (CA): rates page
• SchoolsFirst Federal Credit Union (CA): rates page
• Space Coast Credit Union (FL): rates page
• SRP Federal Credit Union (SC): rates page
• Sunmark Credit Union (NY): rates page
• Together Credit Union (MO): rates page
• Total Mortgage (AL, AZ, AR, DE, GA, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MT, NE, NV, NJ, NM, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WY): one rates page per state, for example totalmortgage.com/locations/state/AL/mortgage-rates
• Tower Federal Credit Union (MD): rates page
• Tropical Financial Credit Union (FL): rates page
• Truity Credit Union (OK): rates page
• U.S. Bank (all 50 states): one rates page per state, for example usbank.com/home-loans/mortgage/mortgage-rates/alabama.html
• University of Hawaii Federal Credit Union (HI): rates page
• University of Michigan Credit Union (MI): rates page
• Vermont Federal Credit Union (VT): rates page
• Virginia Credit Union (VA): rates page
• Washington Trust (CT, MA, NH, RI): rates page
• Wells Fargo (TX): rates page
• Westmark Credit Union (ID): rates page
• Wings Financial Credit Union (MN): rates page

Checked, but no 30-year rate published

• Listerhill Credit Union (AL): Rate table says to call 1.800.239.6033 for the latest 30-year fixed rate.
• Alabama Credit Union (AL): Lists 10, 15 and 20-year rates; says to call the loan department for 30-year fixed rates.

How stage shares are applied in the calculator

The calculator uses the NAHB stage shares as percentages of the total construction cost. For each stage, the national average amount is calculated as:

Stage amount = (stage share % ÷ 100) × base rate per sq ft × total floor area

Within each stage, the sub-category amounts are calculated proportionally to their listed shares, so that the sub-category amounts always sum to the stage total. This is necessary because NAHB figures are rounded and sub-category shares do not always sum exactly to their stage total.

Limits of national averages

As NAHB itself states, the results of the Cost of Constructing a Home survey are national averages and are not a tool for pricing a specific house in a specific location. Actual costs vary significantly by region, local labor market, site conditions, design complexity, and finish level. The calculator is a planning tool and starting point: it is not a substitute for quotes from licensed local contractors.

Using your own quotes

Every stage and sub-category in the calculator can be overridden with your own contractor or supplier quote. Enter a lump-sum quote for a whole stage, or enter individual quotes at the sub-category level. The calculator will use your quotes where you have them and fall back to NAHB national averages for everything else.

What is not included in the construction cost

The NAHB construction cost figure covers the physical construction of the home, including the Site Work stage (building permit fees, impact fees, water and sewer fees and inspections, architecture and engineering) and the Final Steps stage (landscaping, driveway, outdoor structures, clean-up). It does not include: land cost, builder overhead and profit (entered separately in the calculator), site work beyond the average in the NAHB stage shares, or soft costs such as loan interest, insurance, or temporary housing. The land-to-move-in checklist covers these additional cost categories.

How the totals are calculated

Total = land + (construction × (1 + story adjustment) × (1 + overhead & profit)) × (1 + contingency)

Contingency is applied to the building costs only. The land price is usually fixed when you buy, so it is added after the contingency. The budget tab runs the same formula in reverse: it removes the land (if your budget includes it), then the contingency, then overhead and profit and the story adjustment, then subtracts any lump-sum quotes and divides what is left by the cost per square foot.