Tax season 2027: what an accounting firm can automate right now

For a firm, the season does not start when electronic filing opens: it starts the day the first client sends documents, and it is prepared well before that. These are the dates that frame the filing of 2026 returns.

1. Now

   Renew your EFILE registration

   The CRA asks tax preparers to submit their EFILE renewal application as early as possible; the current password only works until January 29, 2027. From January 30, 2027, transmitting an authorization request, including for a business, requires a renewed account, a passed suitability screening and software updated with the newly assigned password.

2. January 29, 2027

   EFILE closes temporarily

   At 11:59 p.m. Eastern time, the CRA temporarily stops accepting T1 and T3 transmissions while it prepares the 2027 program.

3. End of February 2027

   Slips arrive, then the season opens

   Employers and financial institutions issue most slips (T4, T5) and Quebec RL slips (RL-1, RL-3) at the end of February. The CRA and Revenu Québec announce when filing opens: last season, both opened on February 23, 2026.

4. Around mid-March 2027

   Slips are on the CRA’s file

   The CRA says it receives most third-party slips by the end of February and makes them available around mid-March through Auto-fill my return.

5. April 30, 2027

   Filing and payment deadline

   For most individuals: file the 2026 return and pay the balance owing, federally and in Quebec.

6. June 15, 2027

   Self-employed individuals

   Filing deadline for self-employed individuals and their spouse or common-law partner. The balance owing is still due April 30, 2027: a return delivered in June can already carry interest.

1. 1

   Above five returns, electronic filing is mandatory

   The CRA requires it of any tax preparer who accepts payment to prepare more than five returns of one type (T1, T2 or T3) in a calendar year, with a penalty for each return filed on paper (25 dollars per T1). Revenu Québec, for its part, asks preparers who file more than five individual returns to transmit them through NetFile Québec.

2. 2

   The client authorizes the transmission before it goes

   Clients sign Form T183 for the federal return and Form TP-1000.TE-V for the Quebec return, before transmission. The CRA accepts an electronic signature on the T183, and Revenu Québec accepts one on the TP-1000.TE-V. The firm and the client each keep a copy for at least six years after the return is filed.

3. 3

   An electronic signature assumes a verified identity

   The CRA states that it expects identity verification to be performed by the party receiving the signed form, and that some forms require a date-and-time stamp. Keep the certificate of completion from your signing service with the form: it is what proves when the signature was applied.

In many firms, preparing the return is not what wears the team out. Everything around it is:

• chasing documents one by one, by email and then by phone;
• digging through an inbox for an attachment sent three weeks ago;
• keying slips into the tax software, box by box;
• answering “where is my file at?”;
• chasing fees after the return is filed.

These tasks have three things in common: they come back every year, they follow known rules, and a mistake in them is costly. That is exactly what automates well, as long as a professional stays in the right place.

1. Collecting documents through a portal instead of email

A secure client portal replaces attachments: clients drop their documents in one place, and the firm knows what arrived and when. Email was never designed to carry social insurance numbers; an encrypted portal with individual access is a far better answer to the reasonable security measures the law requires of every business.

2. A list of what is missing, computed rather than kept by hand

From last year’s file (slips received, family situation, business or rental income), the system works out what the client should provide this year and shows what is missing at all times. Reminders to the client are drafted by the system, then reviewed and sent by the professional: the tone stays the firm’s, and nobody is chased for a document already uploaded.

3. Signatures and authorizations, electronically

Engagement letter, T183, TP-1000.TE-V, power of attorney: all of them can be signed electronically, with a verified identity and a time stamp, then filed automatically in the client’s record. The firm no longer waits for a crooked scan to transmit a finished return.

4. Reading slips, under control

A T4 or an RL-1 in PDF can be read without AI; AI mostly serves for less regular documents. The check comes from a second source: authorized representatives, through Represent a Client, can import the slips the CRA holds with Auto-fill my return, and download Revenu Québec data with the client’s download code or a power of attorney. A gap between the client’s document and the official data shows up before data entry, not after the notice of assessment. Nothing goes into the return without validation.

5. Fees, up front

Estimate fees from the complexity of the file (number of slips, business or rental income), announce them before starting and collect before delivery: a payment link attached to the invoice beats a list of receivables in May.

6. File status the client can see

Documents received, in preparation, in review, ready to sign: when clients can see the stage their file is at, they call less, and the firm sees at a glance where every file of the season stands.

AI belongs where it is needed: reading, comparing, preparing. It does not replace what makes a firm valuable:

• professional judgment: pension income splitting, choosing deductions and credits, newcomers and non-residents;
• the final review: a professional reads every return before it goes out;
• the relationship: an unexpected notice of assessment, a tax debt or a separation is discussed in person, not through a drafted message;
• edge cases: when a rule is unclear, the professional decides and records the decision in the file.

A tax file holds the most sensitive information a client has: their SIN, their income, their health through medical expenses, their family. In Quebec, the private-sector privacy act requires reasonable security measures, a privacy impact assessment before any information system project that handles this information, and a register of confidentiality incidents. We cover them in our article on Law 25 and AI.

• An encrypted portal for documents, never email for a SIN.
• Individual access and multi-factor authentication, no shared accounts.
• A written retention period: six years for the T183 and the TP-1000.TE-V, and nothing longer without a reason.
• A written contract with every vendor who sees client files, and an additional assessment if the data leaves Quebec.
• A procedure for when a document goes to the wrong person: immediate measures, risk assessment, register.

1. 1Renew your EFILE registration as early as possible (the current password only works until January 29, 2027), then install the 2027 version of your tax software.
2. 2Update your templates: engagement letter, revised T183, TP-1000.TE-V.
3. 3Choose your e-signature service and how you will verify client identity remotely.
4. 4Open the client portal and prepare, for each client, the list of expected documents based on last year’s file.
5. 5Set your fee schedule and the rule of payment before delivery.
6. 6Write down who does what: preparation, review, signature, filing.
7. 7Run a privacy impact assessment for any new tool that touches client files, with your person in charge of the protection of personal information.
8. 8Test everything on three of last year’s files before opening the portal to clients.