I will say this up front. I am not your accountant. What follows is the practical, plain-language version of what most freelancers need to get right on their invoices for tax purposes in the US, the UK and Canada. If your situation is complicated (multi-state, international, S-corp election, anything involving stock options as income) please talk to a real CPA. For everyone else, this is the working baseline.
The tax thing every new freelancer misses
When you are employed, taxes come out of your paycheck before you ever see the money. You barely think about it. When you are a freelancer, nobody withholds anything. The full amount the client pays you arrives in your bank account, and then a chunk of it has to come back out for taxes a few months later.
Rough rules of thumb to keep yourself out of trouble. In the US, set aside 25 to 30 percent of every invoice for federal and state income tax plus self-employment tax. In the UK, plan for 20 to 40 percent for income tax plus 9 percent Class 4 National Insurance once you cross the lower threshold. In Canada, budget roughly 15 to 33 percent federal plus provincial, plus your CPP contributions. None of these are exact (your actual rate depends on your bracket and what you can deduct) but if you set aside nothing, April will be unpleasant.
What a US freelancer's invoice should include
If you are billing US clients as a sole proprietor or single-member LLC, your invoice needs the boring basics, name, address, invoice number, line items, total, plus:
- Your taxpayer ID. Most freelancers use their SSN. If you have an EIN (highly recommended, free from the IRS, separates business identity), use that instead. The client needs it for the 1099-NEC they will file at year-end.
- A W-9 separately. Most clients ask for this once at onboarding. The invoice itself does not include the W-9. Just have one ready to email when asked.
- Sales tax, but only if you actually need to charge it. Most freelance services are not taxable in most US states. New York taxes some IT consulting. Pennsylvania taxes some creative work. Hawaii's GET taxes nearly everything. If you are selling physical goods or digital downloads, economic nexus rules from Wayfair v. South Dakota almost certainly apply once you cross a state's threshold.
What a UK freelancer's invoice should include
- Your business name and address. Your home address is fine for sole traders.
- Your VAT number if you are VAT-registered. The 2026 threshold is £90,000 in taxable turnover over a rolling twelve months. You can register voluntarily below that.
- A VAT line if applicable. Standard rate 20 percent, reduced rate 5 percent on specific items, zero-rated for certain goods and services. The line needs to show the rate and the amount, separately from the net.
- The tax point (date of supply) if it differs from the invoice date.
- A sequential invoice number with no gaps. HMRC explicitly requires this for VAT-registered businesses.
What a Canadian freelancer's invoice should include
- Your business name and address.
- Your GST/HST number once registered. Registration is mandatory once you exceed CAD 30,000 in taxable revenue over four consecutive quarters. Different provinces use different rates: 5 percent federal GST, 13 or 15 percent HST in the HST provinces (Ontario, Atlantic provinces), plus PST or QST in BC, Saskatchewan, Manitoba and Quebec.
- The tax rate(s) and amount. Critical, because your client uses this to claim input tax credits. Get the rate wrong and they cannot reclaim it cleanly.
Quarterly estimated taxes (US)
Do not skip this and do not learn about it the hard way. If you will owe more than $1,000 at year-end, you are supposed to send estimated tax payments four times a year on April 15, June 15, September 15 and January 15 of the following year. Miss them and the IRS adds a small underpayment penalty (federal short-term rate plus 3 percent, applied quarterly).
IRS Form 1040-ES has the worksheet, but the simpler heuristic is to take last year's total tax bill, divide by four, and send that amount each quarter. If your income jumps, recalculate mid-year so you do not under-pay.
Deductions worth tracking
The single biggest mistake new freelancers make is not tracking expenses well, then paying tax on revenue rather than profit. What counts as a deductible business expense, in broad strokes:
- Home office (used regularly and exclusively for work)
- Software subscriptions and tools (Figma, Adobe, ChatGPT, your VPN)
- Computer, phone and headphones, prorated by business-use percentage
- Internet, prorated by business-use percentage
- Professional development: courses, books, conference tickets
- Travel for work, mileage if you drive client-related miles
- Marketing: domain, hosting, ads, business cards
- Health insurance premiums (US has special above-the-line deduction rules for self-employed)
- Retirement contributions (SEP-IRA, Solo 401k in the US; SIPP in the UK; RRSP in Canada)
When to incorporate
For most freelancers, sole proprietor or sole trader is fine. Incorporation makes sense when one of these is true:
- You are consistently making over about $80,000 to $100,000 a year and an S-corp election (US) could save you self-employment tax.
- You have employees or subcontractors and you want legal separation.
- Your work has real liability exposure and an LLC or Ltd shield genuinely matters.
- A client requires you to invoice through a registered company; some larger corporates do not contract with individuals.
Below those triggers, sole prop is simpler, cheaper, and the tax math is roughly the same. Incorporation adds annual filing fees, a separate tax return, and sometimes payroll. Not free.
Three habits that save you in audits
1. Number your invoices sequentially with no gaps. Easiest way to demonstrate you are reporting everything. More on this in the invoice numbering guide.
2. Keep digital receipts for every business expense. Phone photo, attached to a transaction in your bookkeeping tool. Five seconds at the moment of purchase. Saves you days at tax time and rescues you from a guessing game in any audit.
3. Separate your business and personal bank accounts. Co-mingling is the audit bait that costs most freelancers. Every major bank offers free business checking; an hour of paperwork solves the problem permanently.