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How Much Is a Room Addition Permit? (2026)

What a building permit costs for a 400 sq ft room addition ($60,000 construction value), compared across every jurisdiction PermitPrice has verified, with the formula behind each number and how to find the current rate where you live.

Jurisdictions compared
22 (MD, TX, VA), all from official fee schedules
Lowest
$75.00 · Lubbock, TX
Median
$271.00
Highest
$682.81 · Montgomery County, MD
Example project
A 400 sq ft room addition, $60,000
Written By
Munib Ur Rehman · October 2026
Key Takeaways
  • Across 22 verified jurisdictions, a permit for a 400 sq ft room addition ($60,000 construction value) runs from $75.00 (Lubbock, TX) to $682.81 (Montgomery County, MD). The median is $271.00.
  • 1 of the 22 charge a flat fee, from $456.98 to $456.98. 3 price it on the project value; 18 price it by floor area or size tier.
  • Every jurisdiction in the table requires a building permit for a room addition: it adds conditioned floor area to the house, so it is reviewed for structure, energy code, setbacks and egress.
  • A room addition almost always needs separate electrical, mechanical (HVAC) and often plumbing permits, each with its own fee. Zoning or setback review, and in some places impact or utility fees, can also apply. The building permit fee alone is what this page compares.
  • Every figure here is computed by PermitPrice's calculator engine from the jurisdiction's own published fee schedule with the same inputs; the effective date of each schedule is shown in the table. 3 of the 22 rows are computed from schedules dated before 2024 and 2 from schedules with no printed date; those are flagged.
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What This Guide Covers - and What It Does Not

This guide covers: the residential building permit fee for a 400 sq ft room addition ($60,000 construction value), computed with the same inputs for every jurisdiction in PermitPrice's verified calculator data that publishes a fee line for this project type (22 jurisdictions). Size-based schedules use the square footage, value-based schedules use the dollar value, and flat-fee schedules ignore both. Each row links to the jurisdiction page with the full schedule and the official source.

This guide does NOT cover: trade permits (electrical, plumbing, mechanical), zoning or setback review, HOA approval, impact or utility connection fees, reinspection fees, or commercial work. A room addition almost always needs separate electrical, mechanical (HVAC) and often plumbing permits, each with its own fee. Zoning or setback review, and in some places impact or utility fees, can also apply.

Coverage note: PermitPrice covers Virginia, Maryland, Texas and Washington, DC. Jurisdictions outside those states, and covered jurisdictions whose schedule has no separate line for this project type, are not in the table. The range is a range of verified fee schedules, not a national average.

How Jurisdictions Price a Room Addition Permit

The dollar figures look arbitrary until you see the formula behind each one. Every jurisdiction in the table uses one of three methods, and the method matters more than the project.

Pricing methods found in the 22 verified schedules
Flat fee - one published amount for the permit, regardless of project cost or size. 1 of the 22 jurisdictions use it here.
Value-based - a percentage of the declared construction value, or a fee picked from value tiers, often with a minimum and with surcharges on top. 3 of the 22 use it here.
Size-based - a rate per square foot, or a flat amount chosen by size tier. 18 of the 22 use it here. Size-based schedules usually carry a minimum that small projects fall under.

Room Addition Permit Cost by Jurisdiction

Building permit fee for a 400 sq ft room addition ($60,000 construction value), lowest to highest. Each total is computed by PermitPrice's calculator engine from the jurisdiction's published schedule with identical inputs, so the rows are directly comparable. Click a jurisdiction for its full fee schedule and source.

Room Addition Permit, a 400 sq ft room addition, $60,000: 22 verified jurisdictions, sorted by total
Jurisdiction Method Line items All-in total Schedule effective Data quality
Lubbock, TX Per sq ft Building Permit Fee $75.00 $75.00 Oct 1, 2025 Verified
Baltimore County, MD Flat by size tier Building Permit Fee $85.00 $85.00 Nov 26, 2018 Source-age
Grand Prairie, TX Per sq ft Building Permit Fee $100.00 $100.00 Sep 2, 2025 Verified
Fairfax County, VA Per sq ft Building Permit Fee $141.75 + Virginia USBC Code Academy Levy $2.84 + Fairfax County Technology Surcharge $14.18 $158.77 Jul 1, 2026 Verified
Harford County, MD Per sq ft Building Permit Fee $60.00 + Application Fee (non-refundable) $100.00 $160.00 Jan 1, 2025 Verified
Corpus Christi, TX Per sq ft Building Permit Fee $184.40 + 4.5% Surcharge $8.30 $192.70 Oct 1, 2025 Verified
Killeen, TX Per sq ft Building Permit Fee $200.00 + Tech/Application Fee $10.00 $210.00 Oct 1, 2025 Verified
Tyler, TX Per sq ft Building Permit Fee $188.00 + Plan Review Fee $37.60 $225.60 Sep 9, 2026 Verified
Plano, TX Per sq ft Building Permit Fee $192.00 + Plan Review Fee $45.00 $237.00 Nov 1, 2025 Verified
San Marcos, TX Per sq ft Building Permit Fee $252.00 $252.00 Oct 1, 2025 Verified
Georgetown, TX Per sq ft Building Permit Fee $200.00 + Application Fee $60.00 + Technology Fee $10.00 $270.00 Oct 1, 2023 Source-age
McKinney, TX Per sq ft Building Permit Fee $272.00 $272.00 Undated schedule Verified
Irving, TX Per sq ft Building Permit Fee $280.00 $280.00 Feb 13, 2026 Verified
College Station, TX Per sq ft Building Permit Fee $300.00 $300.00 Oct 1, 2025 Verified
Frederick County, MD Flat by size tier Building Permit Fee $276.00 + Filing Fee $33.00 + Automation Enhancement Fee $11.00 $320.00 Jul 1, 2026 Verified
Arlington, TX Per sq ft Building Permit Fee $320.00 $320.00 Sep 1, 2025 Verified
El Paso, TX Per sq ft Building Permit Fee $348.00 $348.00 Sep 1, 2025 Verified
Richmond City, VA Value tiers Building Permit Fee $415.06 + Virginia USBC State Levy $8.30 $423.36 Nov 18, 2013 Source-age
Henrico County, VA Value tiers Building Permit Fee $430.00 + Virginia USBC State Levy $8.60 $438.60 Undated schedule Verified
Chesterfield County, VA Flat fee Building Permit Fee $399.00 + Virginia USBC State Levy $7.98 + Environmental Engineering Site Inspection Fee $50.00 $456.98 Jul 1, 2026 Verified
Anne Arundel County, MD Flat by value tier Building Permit Fee $592.00 + Application Fee (non-refundable) $43.00 $635.00 Oct 1, 2024 Verified
Montgomery County, MD Per sq ft Building Permit Fee $353.22 + DPS Filing Fee $329.59 $682.81 Jul 1, 2026 Verified

Verified = computed from the official fee schedule linked on the jurisdiction page. Source-age = the official schedule is dated before 2024 and may have been superseded; the jurisdiction page discloses the caveat. Undated schedule = the official source shows no printed effective date. Totals use each jurisdiction's own rounding and include only the line items shown.

What Drives the 9x Difference

The same project costs $75.00 to permit in Lubbock, TX and $682.81 in Montgomery County, MD. Four things account for almost all of that gap.

  • Pricing method. A schedule that charges on project value or floor area scales with the job; a flat fee does not. That alone separates the top of the table from the bottom.
  • Stacked surcharges. Virginia adds a 2% state levy on every permit. Some jurisdictions add a plan review fee, an application fee, or a technology fee. Each is a line on the invoice that a headline "permit fee" leaves out.
  • Minimum fees. Where a percentage or per-square-foot rate would produce a small number, the schedule's minimum applies instead.
  • Schedule age. Fee schedules are typically re-adopted each fiscal year (July 1 in Virginia and Maryland, October 1 in many Texas cities). A jurisdiction whose published schedule is several years old may charge more today than the table shows; those rows are flagged.
Find Your Room Addition Permit Fee in Four Steps
1. Confirm a permit is required. Every jurisdiction in the table requires a building permit for a room addition: it adds conditioned floor area to the house, so it is reviewed for structure, energy code, setbacks and egress.
2. Open your jurisdiction's page. Every row above links to a page that states the formula, the effective date and the official source document. If your city or county is not covered, its building department publishes the fee schedule, usually as a PDF or ordinance appendix.
3. Apply the formula to your numbers. Use your contract price for value-based schedules and your floor area for size-based ones. The permit fee calculator does this line by line for every jurisdiction in the table.
4. Add the surcharges and the separate permits. State levy, plan review or technology fee, then any electrical, plumbing or mechanical permit your project needs. Then verify the total with the building department before you budget.

When These Numbers May Not Apply

  • Your project cost or size differs from the example. Flat-fee rows do not change; value-based and size-based rows do. Use the jurisdiction page or the calculator with your own inputs.
  • The building official substitutes a valuation. Value-based jurisdictions may replace a low declared cost with a valuation table figure, raising the permit fee.
  • The schedule has been re-adopted. Rows flagged Source-age or Undated may be higher today. The jurisdiction page shows the last date PermitPrice verified the schedule.
  • Work started before the permit. After-the-fact permits, reinspection fees and penalties are outside every figure on this page.
  • Special districts. Historic overlays, floodplains and HOA covenants add review steps and sometimes fees that the building permit schedule does not include.

Frequently Asked Questions

Between $75.00 and $682.81 for a 400 sq ft room addition ($60,000 construction value) in the 22 jurisdictions PermitPrice has verified, with a median of $271.00. The cheapest charge a flat fee or a low per-square-foot rate; the most expensive price the permit on the project value or floor area and add surcharges. Your own fee depends on which method your jurisdiction uses, so start from its page in the table above.
No. Building permit fees are set by each county or city, usually by ordinance and usually re-adopted every fiscal year. States sometimes add a levy on top (Virginia charges 2% on every permit), but the base fee is always local. That is why the same project costs $75.00 in Lubbock, TX and $682.81 in Montgomery County, MD.
No. A room addition almost always needs separate electrical, mechanical (HVAC) and often plumbing permits, each with its own fee. Zoning or setback review, and in some places impact or utility fees, can also apply.
Usually yes. An addition changes the house footprint or height, so it is checked against setback, lot-coverage and height limits before the building permit is issued. Zoning review fees are set separately and are not included in any total on this page.
Each row shows the effective date of the official schedule it was computed from, and each jurisdiction page shows when PermitPrice last verified that schedule. 3 of the 22 rows are computed from schedules dated before 2024 and 2 from schedules with no printed date; those are flagged. This page was compiled on Oct 5, 2026.
Official .gov Sources · Compiled Oct 5, 2026

The remaining 19 jurisdictions in the table cite their official schedule, with effective and verified dates, on their linked pages.

Other project-type overviews: Deck · Shed · Fence · Pool · Remodel · Roof · Demolition.

Verify current fees directly with your local building department before budgeting or filing an application. Every total on this page is computed from a published fee schedule with the effective date shown; schedules are re-adopted regularly and some rows are flagged as older or undated. The jurisdiction pages list the department phone number and the official document for each row.
Disclaimer: All fee information on PermitPrice is for informational purposes only and is not an official permit quotation. Actual permit fees are determined by the local building department at the time of application. Fee schedules, surcharge rates, and permit requirements can change without notice. Verify all fees directly with the applicable building department before filing.

Written by: Munib Ur Rehman

Data verified against official fee schedule documents.