Do umbrella & agency contractors need to file a tax return?
If you're paid through an umbrella company or agency, your tax and NI are usually deducted at source under PAYE — so it's natural to assume there's nothing more to do. Often that's true. But in plenty of common situations you still need to file a Self Assessment tax return, and getting it wrong can cost you penalties — or a refund you never claimed.
The quick answer
Being on PAYE through an umbrella doesn't automatically remove the need to file. You generally do need a Self Assessment return if any of these apply:
- You had more than one source of income in the year — for example umbrella PAYE plus some self-employed or freelance work.
- You worked under CIS (Construction Industry Scheme) and had 20% deducted — you often file to reclaim overpaid tax.
- You earned over £100,000.
- You had untaxed income — rental income, dividends, savings interest above the allowance, or foreign income.
- You want to claim tax relief on allowable expenses that weren't reimbursed.
- HMRC has asked you to file (you've been issued a notice to complete a return).
Key point for CIS workers: if you're a subcontractor taxed at 20% under CIS, you've very likely overpaid once your personal allowance and expenses are taken into account. Filing a Self Assessment is how you get that money back — often a meaningful refund.
"But my umbrella already deducts tax…"
True — a compliant umbrella runs you through PAYE and pays over your Income Tax and NI. The issue is that PAYE only sees the income it handles. It can't account for a second job, a side trade, rental profit, or expenses you incurred yourself. Self Assessment is how HMRC reconciles your whole tax position for the year — and it cuts both ways: you might owe a little more, or be owed a refund.
What you can often claim
Depending on your situation and how you're engaged, allowable costs might include certain travel and subsistence, tools and equipment, professional subscriptions, and use of home for genuine business work. The rules are strict — and tighter for inside-IR35 and umbrella arrangements than many people assume — so it's worth getting advice rather than guessing. Claiming something you're not entitled to causes more problems than it solves.
The deadlines that matter
| Date | What's due |
|---|---|
| 5 October | Register for Self Assessment (if it's your first time) |
| 31 October | Paper tax return deadline |
| 31 January | Online tax return deadline + pay any tax owed |
| 31 July | Second payment on account (if applicable) |
Miss the 31 January online deadline and you're looking at an automatic £100 penalty, with more piling on the longer it's late — even if you owe no tax.
The bottom line
Being paid through an umbrella or agency doesn't mean you're "sorted" with HMRC. If you had more than one income source, worked under CIS, or have expenses or untaxed income to declare, a Self Assessment return is likely needed — and for CIS workers especially, it's often the route to a refund. The safest move is a quick check rather than an assumption.
Not sure if you need to file?
We handle Self Assessment for contractors, umbrella & agency workers, CIS subcontractors, landlords and directors — fixed fees from £145. Tell us your situation and we'll confirm.
See Self AssessmentGeneral information, not tax advice, and correct to our understanding as at June 2026. Your circumstances may differ — please get specific advice before acting.