T4s that validate before they leave
Year-end built from the pay you actually ran. Every electronic return is checked against the government's own published schema before you download it — and where a filing is not built, this page says so.
T4 and T4 Summary
Electronic return (XML), validated against the CRA's schema, plus employee slips as PDFs.
T4A and T5018
Electronic returns for contractors and construction subcontractors.
RL-1 (Québec)
Employee slips are produced. Electronic transmission awaits Revenu Québec partner registration.
W-2 / W-3
An EFW2 file for the Social Security Administration, for American payrolls.
Filing readiness
Before year-end, one screen lists what would stop a filing — a missing payroll account number, an employee without a SIN — so it is fixed in December, not February.
Frequently asked questions
Can I file directly from SeroPayroll?
You download the validated XML and upload it through the CRA's Internet file transfer. The file is checked against the CRA's schema first, so it is accepted the first time.