Wilmington, DE
Wilmington plumbing permit fees
A plumbing permit in Wilmington costs $20.00 flat.
The L&I fee table prices 'Plumbing' as one amount — not per fixture and not by valuation — so a water-heater swap and a whole-house repipe carry the same printed fee. The identical $20.00 sits beside it for heating, air conditioning and ventilation, which makes the City's trade side a flat-fee schedule in contrast to its value-scaled construction permit.
How this fee is calculated
These are the components the schedule defines for this permit, as they applied on 2026-09-28. A component only applies to your project if its conditions match — read that column before assuming a figure. Want a figure for your own project? Estimate this fee with the permit fee calculator.
| Component | Formula | Applies when | Range |
|---|---|---|---|
| Plumbing permit ($20.00)Permit fee | $20.00 flat fee | Every permit of this type | — |
A real permit fee is these components added together. The department’s final calculation is the one that applies — this is the schedule it will be based on.
A worked example
Follow the arithmetic by hand. Every line is produced by the engine from the rules above, so the total cannot drift away from the schedule behind it.
Worked example
A bathroom remodel adding three fixtures plus a water heater, permitted as plumbing on its own in a single-family dwelling.
| Input | Value |
|---|---|
| Fixtures | 3 |
| Occupancy class | Residential |
Example total
$20.00
An estimate, not an official fee. It is calculated from the published fee schedule as it applied on 2026-09-28. The permit office’s own calculation is the one that applies, and your project may fall under rules this schedule does not describe.
Fee schedule as of 2026-09-28Rules applied 1Rules considered 1
| Component | How it is calculated | Amount |
|---|---|---|
Plumbing permit ($20.00)Permit feeDepartment of Licenses & Inspections fee table, 'Plumbing' row (NEW FEE column, effective June 1, 2014): $20.00. A flat permit fee, not a per-fixture rate — the schedule publishes no fixture count and no valuation band for plumbing. Heating, air conditioning, mechanical ventilation, fire suppression, alarm and refrigeration rows on the same table carry the identical $20.00, which is why the City's mechanical side reads as one flat trade permit.Show the working
| $20.00 flat fee | $20.00 |
| Total | $20.00 |
Assumptions
- Calculated from 1 fee rule in effect on 2026-09-28.
- Amounts are rounded to the nearest cent, once, at the end of each component.
The 'Plumbing' row charges a flat $20.00 — the schedule publishes no per-fixture amount, so the three fixtures and the water heater are one $20.00 permit.
Contrast the band-table cities: a $3,000 standalone plumbing job declared as construction would price at $36.00 on the valuation rate, but the City's own printed plumbing row is $20.00 regardless. If the same remodel were part of a larger $60,000 project, the construction permit would add $720.00 on the building page and the plumbing permit would remain $20.00.
What is different in Wilmington
The plumbing row's structure is the opposite of the construction permit's. The building permit scales at $12.00 per $1,000.00 of cost; 'Plumbing' is $20.00 at any size. The schedule publishes no fixture count, no per-fixture rate and no valuation band for plumbing — there is no row a per-fixture figure could be read from, and none has been printed since the 2014 increase doubled the row from $10.00.
The mechanical rows bracket plumbing on the same table and read the same way: heating installation $20.00, air conditioning system $20.00, mechanical ventilation $20.00, fire suppression $20.00, alarm system $20.00, refrigeration equipment $20.00. A whole-house mechanical-and-plumbing retrofit therefore adds a predictable $20.00 per trade to the budget regardless of scope.
Where the plumbing trade does meet value-sensitive pricing is the construction permit the work usually rides on: if the plumbing is part of a $60,000 remodel, the construction permit on that remodel is charged at $12.00 per $1,000 on the building page here, and the plumbing permit adds its flat $20.00 on top. Sewer and water utility charges are a separate City bill entirely, set by the water utility rather than the L&I table.
What this figure does not include
Impact fees, utility connections and other departments’ permits are the usual omissions, and in some jurisdictions they are larger than the permit fee itself.
Not included in these figures
This is the L&I 'Plumbing' row at $20.00 flat. It excludes:
- The construction permit for the project the plumbing belongs to, at $12.00 per $1,000.00 — charged on the building page here.
- Heating, air conditioning and ventilation permits at $20.00 each, and fire suppression and alarm system rows at $20.00 each.
- Sewer permits and water/sewer/stormwater utility charges, which are Public Works and water-utility bills, not L&I permit fees.
- Certificates of occupancy and compliance on the same page, from $50.00 to $250.00 by type.
- Any per-fixture rate, valuation band or minimum fee — the table publishes none for plumbing, and none is charged.
Common questions
How much is a plumbing permit in Wilmington?
$20.00 flat. The L&I fee table prices 'Plumbing' as a single amount — no per-fixture rate, no valuation band, and no published minimum.
Is there a per-fixture charge?
No. The table publishes one amount for the permit. A one-fixture job and a twelve-fixture job print the same $20.00 plumbing permit.
Does the plumbing permit scale with the project's cost?
No — only the construction permit does, at $12.00 per $1,000.00. The plumbing row is flat at any job size.
What about a water heater replacement?
It is a plumbing permit at the same flat $20.00. The table publishes no separate water-heater row.
Is a sewer connection part of the plumbing permit?
No — sewer permits and the water, sewer and stormwater utility charges are Public Works and water-utility bills, separate from the L&I plumbing permit.
When did the fee last change?
The current $20.00 is from the City's approved increase schedule effective June 1, 2014, which doubled plumbing from $10.00. It is the latest amount the City publishes in an addressable form.
How does a commercial plumbing job get priced?
The same $20.00 flat. The table makes no residential/commercial distinction on any trade row; only the certificate of occupancy schedule differs by building type.
Do I need a plumbing permit for repairs?
Yes — the City requires permits for 'repairs, including electrical, plumbing, and mechanical work', so plumbing repairs are permitted under the trade row.
What other fees attach to finishing the work?
The certificate of occupancy: $75.00 for a dwelling, $100.00 for other buildings, and $100.00 residential / $250.00 commercial for a temporary CO — all on the same L&I page.
Can the plumbing permit ride on the general contractor's building permit?
The table prices the trade as its own permit, so the plumbing permit is its own $20.00 application rather than a percentage or line item of the construction permit.
Source and verification
The documents behind every figure on this page, with the dates that make them checkable.
- City websiteCityPrimary source
Read 2026-09-26 from the City's own URL via its Internet Archive capture of 2026-06-09 (HTTP 200); the live host serves HTTP 403 to scripted requests and the capture is the same document. The page presents every fee in CURRENT FEE / NEW FEE columns dated 'Effective June 1, 2014'; this seed prices the NEW FEE column: permit fees $12.00 per $1,000.00 (from $10.00), plumbing $20.00 (from $10.00), electrical work $20.00 (from $10.00), heating, air conditioning, mechanical ventilation, fire suppression, alarm and refrigeration rows each $20.00. The page states the fees 'coincide with the approved and adopted International Code Council Building Codes'. No minimum fee appears anywhere on the page, and none is charged. This is the most recent fee schedule the City publishes in an addressable form; the department's Construction & Development Review page (read via the 2026-08-14 capture) links fee amounts only through a Step-by-Step Guide document that is itself not addressable HTML.
Verification
Last verified against the official source in Sep 2026.