If you rely on CRA’s online services—My Account, My Business Account, Represent a Client, or the Tax Information Web Service—it’s vital to stay informed about upcoming interruptions. Here’s a clear breakdown to keep your tax filings and online interactions on track.

Scheduled Unavailability Periods

1. Broad CRA Platform Interruptions

• December 23, 2025 (3 AM ET) – January 12, 2026 (6 AM ET)
  Outage affects:
  • File a return, internet file transfers, Web forms, download reports in My Business Account, Represent a Client, TFSA, Partnerships, Contract Payments (T5018), along with payroll and PIER functions. [canada.ca]

2. Non‑Resident Tax Accounts

• December 30, 2025 (12 AM ET) – January 1, 2026 (12 AM ET)
  During these 48 hours:
  • Opening new non-resident tax accounts is unavailable in My Account, My Business Account and Represent a Client. [canada.ca]

3. Personal Tax Slip & Return Services

• January 9, 2026 (11 PM ET) – January 12, 2026 (6 AM ET)
  Affects My Account and Represent a Client:
  • Access to T4 slips, change my return, client data enquiry, carryover amounts, proof of income, return status, and other related services. [canada.ca]

4. Tax Information API / Auto‑Fill‑My‑Return

• January 10, 2026 (11 PM ET) – January 13, 2026 (6 AM ET)
  During this window, the tax information web service (used by certified software to automatically populate returns) will be offline. [canada.ca]

For a smooth CRA experience over the holiday and filing season:

• Mark your calendar with the dates and times above.
• Complete essential tasks early, especially between December 1 and January 9.
• Check back on January 13 to resume full e-service capabilities smoothly.