What must my job reference letter include — and what if my employer won't give one?

Ideally it's on company letterhead and includes your job title, dates, hours per week, salary, main duties, and the company's contact details, signed by a supervisor or HR. If your employer refuses, never create a fake letter — that is misrepresentation. Instead, gather alternatives: employment contracts, pay slips, tax records, and a letter from a supervisor or colleague, plus a short letter of explanation telling IRCC why the standard letter isn't available.