What Documents Does My Tax Preparer Need?

Showing up to tax season with a shoebox of receipts is still common, but it usually leads to delays, missed deductions, and follow-up emails that could have been avoided. If you are asking, what documents does my tax preparer need, the right answer depends on how you earn income, what you own, and whether you have credits, deductions, or filing issues from prior years.

For Canadian taxpayers, the goal is not just to hand over paperwork. It is to give your tax preparer a complete picture of your income, expenses, prior filings, and supporting documents so your return can be filed accurately and with the right tax treatment. A salaried employee, a landlord, a contractor, and an incorporated business owner will not bring the same file.

What documents does my tax preparer need for a basic return?

If your tax situation is straightforward, your preparer will usually start with identification, prior-year tax information, and all current-year slips. That means basic personal details for you and your spouse or common-law partner, including SINs, dates of birth, current address, marital status, and direct deposit details if they have changed.

Your prior-year tax return and notice of assessment are also useful. These documents help verify carryforward amounts, RRSP contribution room, tuition balances, capital losses, instalment requirements, and any CRA issues that still need to be addressed. If you are a new client, this is often one of the first things your accountant will request.

From there, most individuals need their tax slips. Common examples include T4 employment slips, T4A for pension or self-employment-related amounts, T5 investment income slips, T3 trust income slips, T4RSP or T4RIF slips for RRSP and RRIF withdrawals, and government benefit slips such as T4E for employment insurance. If you received social assistance, workers’ compensation, or certain provincial benefits, those may also be relevant even when the amounts are non-taxable.

Personal tax documents that are often missed

Many returns are delayed not because income slips are missing, but because supporting deduction and credit documents were never sent in. Medical expenses are a common example. Your tax preparer may need receipts for eligible expenses not reimbursed by insurance, especially for families with significant health costs.

Child care expenses also matter, particularly for working parents, students, or separated households. If you paid for daycare, day camps, after-school care, or a nanny, keep year-end statements and the caregiver’s business number or SIN where required.

Students and recent graduates should provide tuition slips, student loan interest information, and any unused tuition carryforwards. Home accessibility expenses, charitable donation receipts, union dues not shown on a T4, and moving expenses may also apply. The rule is simple – if it affects taxable income, non-refundable credits, or CRA support requirements, your preparer should see it.

If you sold investments, crypto, or real estate, do not assume the bank slip tells the full story. Your accountant may need trade confirmations, adjusted cost base records, legal closing statements, and dates of acquisition. Tax treatment often depends on the underlying records, not just the proceeds reported.

If you are self-employed, what documents does my tax preparer need?

Self-employed individuals need more than slips. Your tax preparer will need a clear summary of business income and expenses for the year, along with records that support the numbers. This usually includes bookkeeping reports, bank statements, credit card statements, sales records, invoices issued, and receipts for business purchases.

If you operate as a sole proprietor or independent contractor, your preparer will likely ask for a categorized income statement. That means revenue separated from expenses such as advertising, office supplies, vehicle costs, subcontractors, insurance, meals, travel, software, professional fees, and telephone or internet usage. If your books are not organized, the tax filing process becomes slower and more expensive.

Home office claims require additional detail. You may need mortgage interest or rent records, property tax, utilities, insurance, and a reasonable breakdown of the workspace used for business. Vehicle claims also require support. A mileage log, total kilometers driven, business-use percentage, fuel, repairs, insurance, leasing costs, and financing details may all be necessary.

GST or HST matters should not be left out. If you are registered, your tax preparer may also need your GST or HST filings, account numbers, and sales tax collected and paid. This is especially important when income reported on your tax return needs to align with indirect tax filings.

Documents for landlords and real estate investors

Rental income requires more than a rent total from memory. Your preparer will need the property address, ownership percentage, rent collected, and detailed expenses such as mortgage interest, condo fees, repairs, insurance, property taxes, utilities, advertising, and management fees.

There is an important distinction between repairs and capital improvements. Repainting a rental unit may be a current expense, while replacing a roof may need to be treated as a capital addition. That is why invoices matter. The tax result can change depending on the nature of the work.

If you bought or sold rental or personal real estate during the year, provide purchase agreements, sale agreements, legal statements of adjustment, and records of major improvements. For principal residences, reporting may still be required even if the gain is exempt. For investment properties, detailed records are essential for capital gains reporting and potential recapture issues.

Documents for incorporated business owners

If you own a corporation, the list is broader because your accountant may be preparing both corporate and personal returns. At minimum, they typically need the year-end trial balance or bookkeeping file, bank and credit card statements, loan statements, payroll summaries, GST or HST returns, and supporting schedules for major assets, shareholder loans, and retained earnings.

If you paid yourself through payroll, provide T4 summaries and remittance records. If you paid yourself through dividends, include corporate resolutions, dividend amounts, and dates paid. If you introduced funds into the company or withdrew money, your accountant will also need a record of shareholder loan activity. Poor shareholder loan tracking can create avoidable personal tax consequences.

For corporations with inventory, construction contracts, professional billings, or industry-specific reporting, additional support may be required. This is where working with a firm that handles multiple sectors across Canada, such as BOMCAS, can be useful because the file preparation process often changes depending on the type of business and province of operation.

Cross-border, crypto, and other complex situations

Some tax files require specialized documentation from the start. If you worked in another country, owned foreign assets, received foreign pension income, or are a US citizen living in Canada, your preparer may need foreign slips, immigration dates, residency details, and prior cross-border filings.

Cryptocurrency investors and traders should provide transaction histories, wallet records, exchange statements, and records of transfers between platforms. A simple gain or loss summary may not be enough if the preparer needs to verify adjusted cost base, business income treatment, or foreign reporting exposure.

If CRA has sent review letters, reassessment notices, audit queries, or instalment reminders, include those as well. These documents affect how your return is prepared and whether prior issues need to be corrected before filing the current year.

How to organize your tax documents before sending them

A tax preparer does not need perfect bookkeeping from every client, but organized records reduce errors and speed up turnaround. The best approach is to separate documents by category: personal information, income slips, deductions and credits, business records, rental records, investment transactions, and CRA correspondence.

Digital copies are usually preferable if they are clear and complete. Avoid sending random screenshots with missing page totals or unreadable receipts. Label files in plain language so your accountant can identify them quickly. If a number is estimated or incomplete, say so early. It is better to flag a gap than leave your preparer to guess.

Timing also matters. Some slips arrive later in the season, especially T3 slips and certain investment reporting. Filing too early can create amendments later. On the other hand, waiting until the deadline with unorganized records can lead to rushed work, missed planning opportunities, or late-filing penalties if information is incomplete.

The fastest way to know what your tax preparer actually needs

The most accurate answer is always based on your situation. An employee with a T4 and RRSP receipt needs a short list. A self-employed consultant with home office expenses, a rental property, crypto activity, and a spouse with childcare claims needs a much more detailed file.

That is why good tax preparation starts with a document request tailored to the client. A professional accountant should be asking about changes in marital status, property sales, side income, foreign assets, business activity, and prior-year CRA issues before they finalize your return. Tax filing is not just data entry. The quality of the result depends on the quality of the information provided.

If you are unsure whether a document matters, send it and ask. A short question before filing is far cheaper than fixing a return after CRA comes back for support.