Documents for Your Tax Agent in Sri Lanka: A Checklist

Most of the delay in getting a tax return filed has nothing to do with the agent. It's the back-and-forth. The agent asks for a figure, you go looking for it, you send a screenshot, they ask for the one behind it, and a week passes. Multiply that by income sources, expenses, and every certificate you forgot you had, and a filing that should take an afternoon stretches into weeks.

The fix is simple. Hand over a complete package the first time. This is the checklist of documents for a tax agent in Sri Lanka, organised the way an agent actually works through a return, so you can gather everything once and be done.

It applies whether you're a freelancer handing your books to an accountant for the first time, or an agent reading this to send clients a clean list of what you need from them.

What does your tax agent actually need?

At the highest level, a Sri Lankan income tax return is one calculation: add up income from every source, subtract reliefs and qualifying payments, apply the tax rates, then subtract the tax you've already paid. Whatever's left is the balance due.

Your agent can only build that calculation from documents. Every figure on the return has to trace back to something, a bank statement, an invoice, a withholding certificate. So the package you hand over maps directly onto that calculation:

• Income, broken down by source, with foreign currency converted to LKR
• Expenses, for business income, with receipts and an allocation between business and personal use
• Reliefs and qualifying payments you're entitled to claim
• Tax already paid, through APIT, withholding tax, and quarterly instalments
• Your TIN and basic registration details

Get those five things right and the rest is the agent's job. Let's go through each one.

How should you organise your income by source?

Sri Lanka taxes your total income, but the return separates it by source: employment, business, investment, and other income. Your agent needs each source listed separately, with a total they can reconcile against your bank statements.

For each income source, hand over:

• Employment income: your APIT statements or pay records, including any foreign employer payments
• Business income: your invoices and the total revenue received for the year
• Investment income: interest, dividend, and rent statements, plus the related withholding certificates
• Other income: anything that doesn't fit the above, with a short note on what it is

The one that trips people up is foreign income.

How do you handle foreign currency income?

If you're a freelancer or service exporter paid in dollars, euros, or pounds, every receipt has to be converted to rupees before it goes on the return. The rate isn't a year-end average and it isn't the rate on the day you filed. Under Section 26(6) of the Inland Revenue Act, the amount is converted using the Central Bank of Sri Lanka rate on the date the income is taken into account. For individuals on a cash basis, that's the date you received the money.

So a payment of USD 2,000 received on a day the CBSL rate was 300 is recorded as Rs. 600,000. The same USD 2,000 received a month later at a rate of 305 is Rs. 610,000. The dates matter, and so does keeping the evidence.

If foreign income is most of what you earn, our guide to foreign employment income tax in Sri Lanka walks through the conversion rules in more detail.

Which expense records should you hand over?

If you have business income, you're taxed on the profit, not the gross revenue. That means your expenses reduce your tax, but only the ones you can prove and only to the extent they're genuinely for the business.

For every expense you want claimed, your agent needs the receipt or invoice and a sense of how much of it is business. Some costs are entirely business, like a professional subscription. Others are shared, like your home electricity or internet, where only a portion relates to your work.

Group your expenses by category, attach the receipts, and note the business percentage for anything shared. For a fuller list of what's deductible and what isn't, see our guide to what expenses freelancers can deduct in Sri Lanka.

What reliefs and qualifying payments should you list?

Reliefs and qualifying payments reduce your taxable income before the rates apply, so leaving them out means paying more tax than you owe. Your agent applies the ones you qualify for, but they can only apply what you tell them about.

Start with the personal relief. Every resident individual gets a personal relief of Rs. 1,800,000 for the year, deducted automatically from your total income. You don't need to provide anything for it, but it's worth knowing it's there: it's the reason income up to Rs. 1,800,000 carries no tax.

Beyond that, gather proof of anything else you're claiming, such as rent paid, an approved solar installation, or qualifying donations. Each has its own rules and caps, so hand over the supporting documents and let your agent confirm what applies. The figures on these change with the law, so an agent verifying against the current Act is exactly what you're paying for.

How do you prove the tax you have already paid?

This is the section that saves you money, and the one people most often get wrong by under-documenting it. Tax you've already paid during the year is credited against your final bill. Miss a credit and you pay that tax twice.

Three kinds of payment get credited:

The withholding certificates are the easy ones to lose. A bank deducts WHT on your interest, a client deducts it on a professional fee, and each one issues a certificate. Every certificate is a credit your agent can claim, so collect them all before you hand over.

For the quarterly instalments, give your agent the receipt for each payment you made on the four due dates: August 15, November 15, February 15, and May 15. If you're hazy on how those instalments are worked out, our quarterly tax payments guide covers the schedule and the calculation.

Do you need a TIN before your agent can file?

Yes. A Taxpayer Identification Number is mandatory to file an income tax return, and it has to appear on the return itself. Your agent cannot submit anything without it.

If you already have a TIN, just give it to your agent. If you don't, you need to register with the Inland Revenue Department. Anyone liable to file a return must register within 30 days of the end of the tax year, and the number then goes on every return and all correspondence with the IRD.

If you're not sure whether you have a TIN or how to get one, start with our TIN beginner's guide.

When does your agent need everything by?

The annual return for the 2025/2026 year of assessment is due November 30, 2026, eight months after the year ended on March 31. That's the legal deadline under Section 93(1), not the date to start gathering documents.

Work backwards from it. Your agent needs time to build the calculation, ask you about the gaps, and let you find the missing certificate. Handing over a half-complete package in late November is how filings slip past the deadline. Aim to have everything to your agent weeks ahead, so the back-and-forth happens with room to spare.

What does a complete handover package look like?

Put together, a filing-ready package for your tax agent in Sri Lanka contains:

1. Income by source with totals, and foreign income converted to LKR at the date-of-receipt rate
2. Business expenses with receipts and a business-use percentage for shared costs
3. Reliefs and qualifying payments with supporting documents
4. Proof of tax already paid: APIT statements, every WHT certificate, and quarterly instalment receipts
5. Your TIN and registration details
6. A summary of your estimated liability, so your agent has a figure to reconcile against

That last item is optional but powerful. If you can hand your agent a clear calculation of where you think you've landed, their job shifts from building the return from scratch to checking your numbers. That's faster, cheaper, and it catches your own mistakes early.

The goal isn't to do your agent's job. It's to give them everything they need in one go, so the only conversation left is about the tax, not about the missing paperwork. Gather the six items above once, hand them over, and you turn weeks of back-and-forth into a single clean filing.