Most business owners don't need to memorise a filing calendar. They need to know the shape of it — what comes around every month without fail, what's an annual event, and what depends on decisions specific to their business. Exact due dates shift from year to year, sometimes mid-year, so this is deliberately not a list of dates. It's the structure underneath them, so you know what to ask about and when.
The annual event: income tax
Every registered business — sole proprietorship, partnership (AOP), or private limited company — files an income tax return once a year, covering the tax year that's just closed. The return is filed electronically through FBR's IRIS portal, and it's built from your actual books: revenue, expenses, tax already withheld on your behalf during the year, and whatever's left to pay or claim back.
This is the filing most owners are at least vaguely aware of, because it's the one with the biggest single number attached and the most visible deadline. It's also the one that goes smoothest when it's the last step of a process, not the first — a return built from a full year of reconciled monthly books takes an afternoon to prepare. A return built by reconstructing twelve months from bank statements and memory takes considerably longer, and is far more likely to have something wrong in it.
The monthly rhythm: sales tax
This is where most of the actual recurring work sits. If you sell goods, sales tax is federal, filed with FBR. If you sell services, it's provincial — filed with whichever revenue authority covers the province you operate in, not FBR directly. A business that does both files with both, separately, on their own schedules.
Sales tax returns are typically a monthly filing, not annual — which is exactly why the gap between "we'll deal with it later" and "we're behind" closes so fast. Miss one month and you're not catching up on one return, you're catching up on however many have piled up since, each one needing that month's own reconciled sales figures.
Withholding statements
If your business is a withholding agent — and most businesses of any real size are, on at least some categories of payment — you're responsible for deducting tax at source on certain payments (to contractors, on rent, on services from unregistered suppliers, among others) and depositing it, then filing a statement showing what was withheld and from whom. This runs on its own schedule, separate from your sales tax return, and it's easy to lose track of because it's about payments you make, not sales you record.
Payroll-related filings
If you run payroll, salary tax withheld from staff pay gets deposited and reported on its own cadence, alongside EOBI and — depending on your province — a social security contribution. These are monthly obligations tied directly to your payroll run, not something that can be batched up and dealt with quarterly.
The honest bit: exact dates move
Due dates for each of these are set and occasionally revised by FBR and the provincial authorities, and they don't always follow the same pattern year to year — an extension one year doesn't guarantee the same extension the next. Anyone publishing a fixed list of calendar dates on a website is either going to be right by coincidence or wrong by the time you read it. The reliable version of a filing calendar is the one built specifically around your registrations, checked against the current notifications each cycle — which is precisely what a monthly tax filing service should be doing on your behalf, rather than something you're expected to track yourself.
Keep a running log, not a scramble
The businesses that handle this comfortably tend to keep one simple thing: a running log of what's been filed and what's outstanding, updated as each filing happens rather than reconstructed from memory before the next one's due. It doesn't need to be sophisticated — a shared spreadsheet with one row per filing, ticked off as each is submitted, is enough to turn "did we already file that?" from a genuine question into a five-second check.
What this actually means day to day
If there's one thing worth taking from the structure above, it's this: sales tax is the one that punishes delay fastest, because it's monthly and it compounds. Income tax is the one that punishes bad bookkeeping hardest, because a year of disorganised records makes one return disproportionately painful. Withholding and payroll filings are the ones that get forgotten, because they're about money going out, not sales coming in, and they don't show up on a sales report.
Keeping all four aligned is mostly a bookkeeping discipline, not a tax one — the filing itself is usually the easy part once the numbers underneath it are actually right.
See Tax filing for how we handle this month to month, or Bookkeeping if the numbers underneath aren't there yet.