Due: 6 October, 2026.
Remember to include overseas income where relevant, and make sure you also state any tax paid.
Personal Information
Before you start, check the Isle of Man Income Tax Division (ITD) holds the correct details. If anything has changed, update it first.
☐ Full name, address, NI/tax reference
☐ Marital status (for joint assessment considerations)
☐ Residency status for the tax year
☐ Bank details for repayments
☐ Tax agent details (if filing on your behalf)
Employment Income
For employment income, gather the documents below so the figures reconcile cleanly.
☐ T14(s) from all employers showing gross pay (including bonuses), NI and ITIP deducted
☐ Employer benefits (company car, fuel, accommodation, company pension)
☐ Expenses reimbursed / allowances received
☐ Termination payments / redundancy
Bank Interest and Savings Interest
Next, confirm interest income across local and offshore accounts. Also note that some items treated as tax-free elsewhere may not be tax-free in the Isle of Man.
☐ Bank/building society interest (gross figures) – bank statements may be needed
☐ Offshore account interest
☐ Fixed-term / savings bond income / UK PEPs and ISAs (not tax-free in the IOM)
☐ Joint account splits confirmed
Business, Trust and Investment Income
If you have business or investment income, make sure you have the supporting documents and calculations ready.
☐ Accounts for the year (profit & loss) where available
☐ Net taxable profit calculation (adjusted for private use, capital allowances and losses utilised)
☐ Dividends (business, IOM, UK, overseas)
☐ Interest from investments
☐ Annual portfolio statements, tax vouchers and coupons
Other Income
In addition, check whether you have any of the following income sources to declare.
☐ Rental income and related expenses – letting agent statements, loan interest statements, and days vacant schedule may be needed
☐ Income from homestay / TT visitors (tax-free up to £2,350), including relevant expenses and days let
☐ State pension (tick the box if received)
☐ Private pensions (occupational pensions, lump sums taken, annuities) – statements
Deductions, Reliefs, Allowances and Credits
Finally, review deductions and allowances carefully so you don’t miss claims you’re entitled to.
☐ Salary sacrifice arrangements (pension contributions, childcare, cycle-to-work)
☐ Loan and mortgage interest statements or agreements (if applicable)
☐ Charitable donations (receipts where available)
☐ Employment expenses (professional subscriptions, clothing and work tools)
☐ Dependent Relative allowance
☐ Child allowance
☐ Disabled Person’s allowance (medical evidence / disability registration may be needed)
☐ Single parent allowance (form R135)
☐ Cohabiting Couples allowance (form R136)
Practical Tips
☐ Chase T14s and statements early
☐ Take care with joint income splits
☐ Confirm offshore interest (easy to miss)
☐ File early for faster processing and refund payment
