A plumbing business runs on expensive tools, a parts-stocked truck, and a calendar full of supply-house runs. Most of what you spend to do the work is deductible, but only if you track it. This page matches common plumbing costs to Schedule C categories, explains the IRS rules behind each deduction, and shows how to set up records that are easier to defend.

Why should plumbers track business expenses?

Plumbers carry higher overhead than most service trades: a service van, thousands of dollars in tools, a rolling inventory of fittings and fixtures, license renewals, and insurance that covers both the truck and the work. Untracked receipts can mean missed deductions at tax time.

The federal rule is straightforward. To deduct an expense, the IRS requires it to be ordinary and necessary for your trade or business. For a plumber, that covers a pipe wrench, a sewer camera, a roll of PEX, the gas to drive between calls, and the liability policy that keeps you working. It does not cover the boat you take out on Sundays.

Clean records do two jobs. They lower your tax bill by making sure no deduction gets missed, and they protect you if the IRS asks questions later. The foundation is mechanical: a dedicated business checking account, a business debit card for the supply house, and a habit of capturing receipts the day they happen.

What business expenses can plumbers deduct?

Most plumbing business expenses fall into a handful of Schedule C categories. Here is what belongs in each one.

Tools and equipment. Pipe wrenches, channel locks, tubing cutters, pro-press tools, drain snakes, inspection cameras, torches, and test gauges. Hand tools and smaller power tools are typically expensed in the year you buy them. Bigger purchases, such as a trailer-mounted jetter, a mini-excavator, or a heavy press tool kit, usually get depreciated or written off under Section 179 (covered below).

Vehicle expenses. Your service van is one of the largest deductions you have. Payments or lease, fuel, oil changes, tires, repairs, registration, commercial auto insurance, and parking all count. You can choose the standard mileage rate or the actual expense method, but IRS rules limit when you can switch methods for the same vehicle.

Materials and supplies. Copper, PVC, PEX, ABS, fittings, valves, fixtures, solder, flux, sealants, and anything else you buy at the supply house to install on a job. If you bill the customer for materials, you still deduct what you paid for them.

Licensing, bonding, and continuing education. State and local plumbing license fees, master plumber exam fees, bond premiums, backflow certifications, and CEU courses required to keep your license active.

Business insurance. General liability, commercial auto, workers' comp if you have employees, and any inland marine policy covering tools in the truck.

Phone, software, and dispatch tools. Your business cell line, field-service software (Jobber, Housecall Pro, ServiceTitan), accounting software, GPS tracking, and any lead-generation subscription.

How do vehicle and mileage deductions work for plumbers?

The IRS gives you two ways to deduct a work vehicle, and the choice matters.

The standard mileage rate is a flat per-mile amount the IRS publishes every year. You multiply business miles by the rate and that is your deduction. Simple, but you have to log the miles.

The actual expense method adds up the vehicle's annual costs, including fuel, insurance, repairs, depreciation, and lease payments, and deducts the business-use percentage. This can produce a larger deduction for some heavy service vans with high fuel and maintenance costs, but it requires more recordkeeping.

A wrapped van used only for plumbing jobs may support a 100% business-use position, but you still need records showing it was not used for personal driving. A pickup you also drive your kids around in is a mixed-use vehicle, and you'll need a mileage log to split it.

Parking, tolls, and DOT inspection fees are deductible on top of either method. So is the loan interest on a financed van, prorated for business use.

Track mileage from January 1, not when you remember in March. A mileage-tracking app or the mileage feature inside your accounting software can do the job. A paper logbook in the glovebox still works if you actually fill it out.

How does Section 179 apply to plumbing tools and equipment?

Plumbers buy tools constantly. The tax treatment depends on cost and useful life.

Small tools, such as a new pipe wrench, a torch kit, or a set of basin wrenches, are expensed in the year purchased under the de minimis safe harbor. Plumbers who make the IRS de minimis safe harbor election and do not have an applicable financial statement can generally expense eligible tangible property costing $2,500 or less per invoice or item.

Larger equipment with a useful life beyond one year (like a $9,000 sewer camera, a $15,000 jetter, or a trailer-mounted excavator) would normally be depreciated over several years. Section 179 lets you skip the depreciation schedule and deduct the full cost in the year you put the equipment into service, up to an annual cap.

Keep receipts and write a short note on each major purchase: which truck it lives in, what kind of work it does, the date it went into service. If a tool gets stolen out of the truck or damaged on a job, the replacement cost is also deductible, and the loss itself may be deductible to the extent it isn't covered by insurance.

Can plumbers claim a home office deduction?

A plumber who dispatches calls, stores inventory, does the books, or meets with clients at home may qualify for the home office deduction. The IRS sets two tests: the space must be used regularly and exclusively for business. A spare bedroom that doubles as a guest room fails the exclusive test. A converted garage corner with shelving for fittings, a desk for invoicing, and nothing personal in it passes.

Two methods are available. The simplified method deducts $5 per square foot, up to 300 square feet, capped at $1,500 per year. The actual expense method deducts the business-use percentage of rent or mortgage interest, utilities, internet, homeowners insurance, and depreciation. For most one-truck operations, the simplified method is faster and rarely leaves much on the table.

Administrative costs that aren't tied to the home office are fully deductible on their own: accounting software, your bookkeeper, tax prep fees, office supplies, business banking fees, and the laptop you use to run the back office.

What plumbing expenses get missed most often?

These are the ones that get left off Schedule C year after year.

• Uniforms and branded workwear. Logoed uniforms may qualify when they are required for work and not suitable for everyday wear; ordinary clothing, such as plain jeans, generally does not.
• Safety gear. Steel-toe boots, knee pads, cut-resistant gloves, respirators for sewer work, safety glasses, hard hats, hearing protection.
• Bank and payment processing fees. Monthly account fees (if any), wire fees, the 2.9% your card processor takes on every customer payment, ACH fees, and merchant account costs.
• Advertising. Truck wraps and lettering, yard signs at job sites, Google Local Service Ads, Angi or Thumbtack lead fees, sponsored Nextdoor posts, and your website hosting.
• Subcontractor payments. If you pay a helper, a drain-cleaning specialist, or another licensed plumber as a 1099 contractor, those payments are deductible.

How can plumbers track business expenses?

The system matters more than the software. This setup creates cleaner records for an audit and makes quarterly tax estimates easier to prepare.

1. Open a dedicated business checking account. Run every business charge through it. Separating personal and business transactions makes bookkeeping easier to review and reconcile.

2. Use a business debit card at the supply house. Ferguson, Home Depot Pro, your local wholesale counter: pay with the business card every time. The transaction shows up in your business account, and you or your accounting software can categorize it as supplies.

3. Snap a photo of every receipt. Thermal paper fades fast in a hot truck. Most accounting apps will scan and attach the image to the matching transaction.

4. Reconcile monthly. Match every transaction to a receipt and a category. If you wait until April, you will guess, and guesses lose deductions.

5. Connect your bank to your books. QuickBooks, Xero, and Wave all pull transactions directly from a connected business account. Categorize once, and the rules apply to every future charge from that vendor.

6. Set aside tax money as it comes in. Earmarking funds for estimated taxes inside your checking account prevents the April scramble. Allocate a percentage of each deposit to a tax Reserve within your Novo checking account based on your expected tax rate and your CPA's guidance. This works the same way as the business sub-accounts method many trades operators use to bucket money for taxes, payroll, and equipment.

A copy-ready expense tracker

Paste this into your records or hand it to your bookkeeper as a starting categorization.

PLUMBING BUSINESS EXPENSE CATEGORIES (Schedule C)

Line 8  - Advertising: truck wraps, yard signs, Google LSA, lead fees
Line 9  - Car & truck: standard mileage OR actual expenses (pick one)
Line 13 - Depreciation / Section 179: jetters, cameras, excavators
Line 15 - Insurance: general liability, commercial auto, inland marine
Line 16 - Interest: vehicle loan interest (business %)
Line 17 - Legal & professional: bookkeeper, CPA, attorney
Line 18 - Office expense: software, supplies, postage
Line 20 - Rent: shop, storage unit, equipment rental
Line 21 - Repairs & maintenance: truck repairs, tool repairs
Line 22 - Supplies: pipe, fittings, fixtures, solder, PEX, PVC
Line 23 - Taxes & licenses: plumbing license, bond, registration
Line 24 - Travel & meals: out-of-town jobs only
Line 25 - Utilities: shop power, business phone, internet
Line 26 - Wages: W-2 employees (not subcontractors)
Line 27a - Other: uniforms, safety gear, dues, continuing ed

Subcontractors paid $600+ for the year: issue Form 1099-NEC by Jan 31

Drop that block into ChatGPT or Claude with a prompt like "Turn this into a Google Sheet with one tab per category, monthly columns Jan–Dec, a totals row, and a summary tab that adds each category for the year" and you'll get a working spreadsheet you can import. Ask for an Excel file or a fillable PDF instead if that fits your workflow.

How does Novo help plumbers manage expenses?

Novo is a business checking platform built for small operators, including one-truck plumbing shops and growing crews.

• $0 monthly fee and no minimum balance requirement. Useful when cash flow swings with the season and you don't want overhead chewing into a slow February.
• Integrations with QuickBooks, Xero, Stripe, and Shopify. Transactions can sync into QuickBooks or Xero, where vendor rules can help categorize repeat supply-house purchases.
• Novo Reserves. Use Novo Reserves, a budgeting feature within your Novo checking account, to earmark funds for quarterly estimated taxes, payroll, or a new jetter. Allocate a percentage of every customer payment to a tax Reserve before you spend it.
• No-cost incoming wires and built-in invoicing. Helpful when a commercial GC pays a five-figure progress draw, or when a property manager only pays by ACH. See the business wire transfer guide for fees and timing on outbound wires.
• Cash deposits. Novo does not accept cash deposits, which matters for plumbers who collect cash on residential service calls. A common setup pairs a credit-union account for cash with Novo for card payments, ACH, incoming wires, invoices, and bookkeeping integrations.

Novo has a $0 monthly fee, no minimum balance requirement, and integrations with QuickBooks, Xero, Stripe, and Shopify.

What questions do plumbers ask about business expense deductions?

Can a plumber deduct the cost of their work truck?

Yes. A service van or work truck used for the business is deductible either through the standard mileage rate or the actual expense method. A work truck or service van used only for business may be deducted at 100% business use, subject to the deduction method, vehicle rules, and records that support the business use. A mixed-use truck is deducted at the business-use percentage based on a mileage log.

Are plumbing tools a one-time deduction or depreciated?

It depends on cost. Smaller tools eligible under the de minimis safe harbor (generally items costing $2,500 or less per invoice or item, when the election is made) are expensed in the year purchased. Section 179 lets a plumber deduct the full cost of qualifying equipment in the year it is placed in service, up to an annual cap, instead of depreciating it over multiple years.

What expenses can a self-employed plumber write off?

Tools, materials, the work truck, fuel, insurance, license fees, continuing education, business insurance, uniforms with a company logo, safety gear, phone and software, advertising, subcontractor payments, bank and processing fees, and a home office if the space qualifies. Personal expenses and commuting from home to a regular workplace do not count.

Do I need receipts for every expense?

The IRS requires documentation for deductions. For some expenses under $75, documentary evidence may be less formal, but you still need records showing the amount, date, place, and business purpose; keeping the receipt is safer. Snap a photo the day of purchase and store it with the transaction in your accounting software.

Can I deduct my phone if I use it for personal calls too?

Yes, at the business-use percentage. If your phone is roughly 80% business calls, texts, and field-service app use, you deduct 80% of the bill. A second line used only for the business is fully deductible.

When do I have to issue a 1099 to a subcontractor?

If a plumbing business pays a reportable nonemployee $600 or more during the calendar year for services, it must issue Form 1099-NEC to the payee and file a copy with the IRS by January 31 of the following year. Get a W-9 from every subcontractor before you pay them so you have the information ready.

Can I deduct meals on a job?

Generally no, if you're working in your normal service area. Meals are deductible at 50% when you travel overnight for business, or when you take a client out for a business meal. Lunch between calls at the local deli is not deductible.