Invoice for Hours Worked: How to Bill Time (With Template)

An invoice for hours worked is a bill that charges a client for the time you actually spent on their job, line by line, at an agreed hourly rate. It sounds simple. Yet hourly invoices are the ones clients question most: “What was this 3.5 hours on Tuesday?”

Get the format right and those questions disappear before anyone asks them. This guide is for contractors, freelancers, virtual assistants, tradespeople, tutors and consultants who bill by the hour. You’ll learn exactly what to include, how to convert and round time, and you’ll see a real worked example you can copy.

Quick answer: An invoice for hours worked lists each date, a short task description, the hours spent (in decimals), your hourly rate and the line total, then adds a subtotal, any tax, payment terms and how to pay. Attach or summarize your timesheet so the client can verify every hour before paying.

What is an invoice for hours worked?

It’s a time-based invoice. Instead of one flat project fee, the total is simply hours multiplied by rate. Cleaners, IT consultants, handymen, bookkeepers, tutors, lawyers and VAs all bill this way.

The real difference from a standard invoice is evidence. A fixed-price invoice can say “Website redesign: $2,400” and be done. An hourly invoice has to show where every hour went, because the client is paying for time they didn’t watch you spend.

One caveat: if you’re an employee, your hours go on a timesheet for payroll, not on an invoice. Invoicing for time is for independent contractors and businesses billing their clients.

What should an invoice for hours worked include?

At minimum, it needs your details, the client’s details, a unique number, the billing period, itemized time entries and clear payment terms. Here’s the full checklist:

• Your business details: name, address, email or phone, plus a tax ID or VAT number if you’re registered.
• Client details: company name and the person who approves invoices.
• Invoice number and date: sequential and unique, for example 2026-041.
• Billing period: the exact dates covered, such as 3–7 Nov 2026.
• Time entries: one line per date or task with date, description, hours, rate and amount.
• Separate rates: if travel, after-hours or overtime work is billed differently, give it its own line.
• Expenses and materials: listed separately from labor, ideally with receipts.
• Totals: subtotal, tax (if applicable) and total due.
• Payment terms: Net 14 or Net 30, plus the actual due date.
• How to pay: bank details, payment link or accepted methods.

Requirements vary by country. In the UK, the government lists the information an invoice must contain in its guide to invoicing and taking payment from customers. In the US there’s no single federal invoice format, but the IRS expects you to keep records that support your income, as its recordkeeping guidance explains. A timesheet-backed invoice is exactly that kind of record.

If you need a refresher on invoice basics in general, see our guide to the best way to create an invoice. This article focuses only on what changes when you bill by time.

How do you calculate hours on an invoice?

Convert minutes to decimal hours by dividing them by 60, then multiply by your rate. For example, 2 hours 40 minutes is 2 + (40 ÷ 60) = 2.67 hours. At $45 an hour, that’s about $120.

Be careful with rounding decimals, though. 2.67 × $45 is $120.15, while the exact time (2.6667 hours) is $120.00. Over a month of entries, those pennies add up, and a sharp-eyed client will notice. That’s why most people bill in fixed increments instead.

Common minute-to-decimal conversions

• 6 minutes = 0.1 hours
• 10 minutes = 0.17 hours
• 15 minutes = 0.25 hours
• 20 minutes = 0.33 hours
• 30 minutes = 0.5 hours
• 40 minutes = 0.67 hours
• 45 minutes = 0.75 hours
• 50 minutes = 0.83 hours

Should you round billable time?

Yes, as long as your rounding rule is written into your quote or contract and applied consistently. Rounding is normal; surprise rounding is what causes disputes.

Here’s how much the rule matters. The table shows one job that took 2 hours 7 minutes, billed at $60 an hour:

The spread from $120 to $180 is huge for the same 127 minutes. In practice, 15-minute increments are the easiest to explain. If you need a one-hour minimum for call-outs, list it as a “minimum call-out charge” rather than quietly rounding every entry up.

How to write an invoice for hours worked, start to finish

The process is the same whether you bill weekly, every two weeks or monthly. Work through it in this order:

1. Track time as you work. Log start and stop times on the day, not from memory on Friday. Memory consistently under-counts short tasks like calls and emails.
2. Group entries by date or task. Daily lines suit trades and on-site work. Task lines suit project-based knowledge work.
3. Write descriptions the client recognizes. “Installed 3 upper kitchen cabinets, adjusted hinges” beats “Work.” Aim for 5–12 words per line.
4. Convert to decimals and apply your rounding rule. Use the same increment on every line.
5. Apply the right rate to each line. Standard time, travel and overtime each get their own rate if your agreement says so.
6. Add expenses, subtotal and tax. Keep materials separate from labor so the client sees what they paid for your time.
7. Add terms, a due date and a way to pay, then send it promptly. Send it the day the billing period closes and attach the timesheet or a summary of it.

Need a basic layout first? Our guide to free invoice templates for small business covers the standard fields; then add the time columns described here.

Example: an hourly invoice, line by line

Here’s a weekly invoice a drywall contractor might send for 3–5 November 2026, billed in 15-minute increments at $55 an hour, with travel at $30 an hour:

• Mon 3 Nov: Site prep, removed damaged drywall in hallway: 4.5 h × $55 = $247.50
• Tue 4 Nov: Hung 14 sheets of drywall, hallway and closet: 6.0 h × $55 = $330.00
• Wed 5 Nov: First coat of tape and mud, all seams: 3.25 h × $55 = $178.75
• Wed 5 Nov: Travel to supplier for extra joint compound: 0.75 h × $30 = $22.50
• Labor subtotal: 14.5 hours = $778.75
• Materials at cost (receipts attached): $142.60
• Total due: $921.35, Net 14, due 19 Nov 2026

Notice three things. First, travel is on its own line at a lower rate, so the client never feels charged full price for driving. Second, materials sit outside the labor subtotal, which makes the hourly part easy to check. Third, 3.25 hours shows the 15-minute rule in action, so nothing looks arbitrary.

Tax treatment depends on where you are and what you sell, so add sales tax or VAT only if it applies to your services.

What mistakes delay payment on an hourly invoice?

The biggest one is a single lump line like “38 hours: $2,280.” It forces the client to ask for a breakdown, and that question alone can add a week to your payment.

Other common payment-delayers:

• Vague descriptions: “Admin” or “Misc” invites pushback. Name the task.
• No billing period: the client can’t match your hours to their own records.
• Labor and materials mixed together: it hides your real rate and looks like padding.
• Inconsistent rounding: 15 minutes on one line, rounded-up hours on the next.
• No due date: “Payable on receipt” is often read as “whenever.” Give a date.
• Invoicing late: a three-week-old invoice for last month’s hours feels less urgent to the person paying it.

If an invoice does go overdue, use one of our late payment reminder email templates. And for longer hourly jobs, consider taking money up front; here’s how to invoice for a deposit properly.

Should you bill by the hour or by the project?

Bill hourly when the scope is unclear or likely to change, such as repairs, ongoing support, research or anything where you can’t see the whole job in advance. Bill per project when the scope is well defined and you’re fast at it, because hourly billing penalizes your efficiency.

Many people use both. They quote fixed prices for defined packages and fall back to hourly for “anything outside scope.” Either way, your hourly rate needs to cover taxes, unbilled admin time and time off, not just the work itself. Our free freelance day rate calculator works that number out from your income goal.

A faster way to invoice for hours worked

If you’re rebuilding the same hourly invoice in a word processor every week, you’re losing billable time to admin. The Editable Timesheet Invoice Template and Contractor Work Hours Tracker combines both jobs in one file. You log dates, tasks, hours and rates, and it calculates the line totals and invoice total for you.

It’s built for exactly the setup in the example above: one line per day or task, separate rates where you need them, and a clean layout a client can check in seconds. Prefer to shop elsewhere? You can also grab it on our Etsy shop.

Frequently asked questions

How do I write an invoice for hours worked?

List your business and client details, an invoice number, the billing period and one line per date or task showing hours, rate and amount. Then add a subtotal, any tax, a due date and payment instructions. Attaching your timesheet makes approval much faster.

How do I show overtime on an invoice?

Put overtime on its own line with its own rate, for example “Sat 8 Nov, emergency callout: 3.0 h × $82.50 (1.5× rate).” Only charge it if your quote or contract mentions overtime or after-hours rates, otherwise expect a dispute.

Do I need to attach a timesheet to my invoice?

It isn’t always required, but it’s strongly recommended for hourly work. A timesheet lets the client verify your hours without emailing you, and it doubles as a business record for your own taxes and any later disagreement.

How do I invoice in 15-minute increments?

Round each entry to the nearest quarter hour (0.25, 0.5, 0.75) and state the rule on your quote, for example “Time billed in 15-minute increments.” Apply it to every line, then multiply the decimal hours by your rate.

Can I bill a client for travel time?

Yes, if you agreed it in advance. Many contractors bill travel at a reduced rate or a flat trip fee and list it separately from on-site work, so the client can see exactly what they’re paying for.

Send your next hourly invoice with confidence

A good invoice for hours worked answers the client’s questions before they ask them. That means clear dates, plain-English tasks, consistent rounding and a firm due date. Set your rounding rule today, track time on the day, and send each invoice the moment the period closes.

Want to skip the setup? Start with the timesheet invoice template and have your next invoice ready in minutes.