Estimate how much of each month's receipts to move into a separate account for sales tax, corporate tax and accounting fees, and what is left to run the business.
Corporations that run into trouble at year end are often profitable on paper but have spent the GST/HST they collected and have nothing saved for the corporate tax balance. This calculator helps you set a monthly transfer into a separate savings account so the money is there when the returns, instalments and the accountant's invoice arrive.
Formula. Set-aside = money received x your set-aside percentage + monthly accounting and software costs. Left for operations = money received - set-aside - other fixed costs you enter.
How to choose the percentage. Start with the sales tax you actually collected: in a 13% HST province, $20,000 received including tax contains about $2,301 of HST ($20,000 x 13 / 113). Then add an allowance for corporate income tax on the profit you expect. Your accountant can give you a percentage based on last year's return.
Worked example (illustrative). $20,000 received, 18% set-aside, $350 a month for accounting and software: $3,600 + $350 = $3,950 goes to the tax account and $16,050 is left for operations.
Limits. This is a cash-flow habit, not a tax calculation. Input tax credits reduce the GST/HST you remit, and corporate tax depends on profit, not receipts. If the CRA requires instalments, pay them on the instalment dates. See the filing calendar.
Fees, Cost Drivers and 2026 Rules
The T2 due date, balance-due day, instalments, GST/HST returns, T4 and T5 slips and electronic filing and payment rules that set your corporation's 2026 accounting calendar.
Fees, Cost Drivers and 2026 Rules
How the CRA assigns annual, quarterly or monthly GST/HST reporting, when registration is required, how QST works in Quebec, and what each frequency costs in time.
Mistakes, Penalties and Official Sources
How the CRA calculates late-filing penalties on corporate T2 and GST/HST returns, repeat penalties, e-filing and payment penalties, interest, and when relief may be available.
