Billing

What does time and materials mean in construction?

Time and materials is a pricing method where the customer pays for labor hours at set rates plus the cost of materials actually used, so the price is known only after the work is done.

Strapped lumber, concrete blocks and a parked telehandler in a commercial construction staging area.
Material quantities, delivery timing and equipment availability shape the next phase of work. AI-generated illustration.

Time and materials (T&M) is a way to price work when the scope cannot be pinned down. Instead of quoting one number, the contractor tracks every labor hour and every part, and bills them at agreed rates. It shows up in three places: as a full T&M contract, as the pricing method for a change order when the extent of extra work is unknown, and as the normal way small service jobs get billed.

This page is about making T&M billing work: setting rates, capturing the hours, and getting paid for them.

Building a T&M rate

A T&M labor rate has to cover far more than the wage. Federal rules describe the same idea: under FAR 16.601, T&M hourly rates include wages, overhead, general and administrative expenses, and profit. A simple build-up for a private job looks like this:

Example: building a carpenter's T&M rate
ComponentPer hour
Base wage$34.00
Labor burden (payroll taxes, insurance, benefits) at an assumed 35%$11.90
Company overhead share$9.00
Profit$7.00
Billed T&M rate$61.90

The 35 percent burden above is an example only. Calculate yours from your own payroll, workers' comp, and benefit costs; see labor burden and burden rate.

A worked T&M invoice

Say a remodeler opens a bathroom wall and finds rotted subfloor. The contract says hidden conditions are billed at T&M. The crew spends 14 carpenter hours at $61.90 and 6 laborer hours at $44 on the repair, and uses $620 of lumber and fasteners, billed at cost plus 10 percent.

  • Carpenter labor: 14 hours times $61.90 equals $866.60
  • Laborer: 6 hours times $44 equals $264.00
  • Materials: $620 plus 10 percent equals $682.00
  • Total T&M charge: $1,812.60

The invoice goes out with the signed daily tickets, photos of the rot, and the lumber receipts. That backup is what turns a T&M bill from a debate into a payment.

Notice the materials markup in this example. Some contracts allow it, some do not, and some cap it. If the contract is silent, agree on it in writing before the wall is opened, or expect the customer to question it.

Tracking mistakes that cost money

  1. Hours logged at the end of the week from memory. Record them daily, by task, on the ticket.
  2. No customer signature. Get the owner or GC's rep to sign each day's ticket while the work is fresh.
  3. Small materials forgotten. Screws, blades, and caulk add up. Track them or build a consumables percentage into the agreement.
  4. Mixing T&M and contract hours under the same cost code, so nobody can tell what was extra.
  5. Billing late. A T&M bill sent 60 days after the work is much easier to dispute.

Related terms

T&M pricing ties into job costing, hourly rate, and concealed conditions. For a field-tested process, see how to track time and materials work accurately. Smart Business Automator ties T&M tickets to job costs and pulls them straight into the invoice; see job costing and WIP automation.

Frequently asked questions

How do you bill time and materials in construction?

Track labor hours by worker and classification and materials by receipt, then bill hours at the agreed rates and materials at cost plus any agreed markup, with signed tickets and receipts attached.

What markup is used on materials in T&M work?

Whatever the contract states. Some contracts allow a percentage markup on materials, some bill materials at cost and put all margin in the labor rate. Agree on it in writing before work starts.

Is time and materials good for the contractor?

It protects the contractor from scope risk, but only if rates are set correctly and hours are documented. Weak tracking turns T&M into the riskiest way to work.

Can T&M have a cap?

Yes. Many T&M agreements include a not-to-exceed amount. Watch the running total and ask for an increase in writing before you reach it.

Sources

  1. Acquisition.gov: FAR 16.601, Time-and-materials contracts
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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