TFSA Calculator Canada

Important note

Over-contributing is the expensive TFSA mistake. CRA charges a tax of 1% per month on the highest excess amount in your account for each month the excess stays there — $1,000 over your room costs $10 a month — and the tax is reported on Form RC243 (TFSA Return), due by June 30 of the following year. The fix is simple but time-sensitive: withdraw the excess as soon as you spot it, because the 1% keeps accruing for every month the money remains. Note the trap behind many over-contributions: withdrawing money and putting it back in the same calendar year counts as a fresh contribution, because withdrawn room only returns on the next January 1.

How this calculator works

This calculator does two pieces of arithmetic on the room figure you provide. "Remaining room" is max(room - contribution, 0): your available room minus the planned contribution, never below zero. "Percentage of room used" is (contribution / room) x 100, shown with one decimal — so you see how much of your available room a planned contribution would consume.

The room figure comes from you, because only CRA knows your history. For 2026 the rules behind it: $7,000 of new annual room; a cumulative lifetime limit of $109,000 if you were 18+ and a Canadian resident in every year since 2009 and never contributed; unused room carries forward indefinitely; and withdrawn amounts become new room on January 1 of the following year — not immediately.

Two traps the math reveals: only contributions consume room, not growth — a $7,000 contribution that grows to $9,000 used just $7,000 of room. And the percentage can exceed 100%: a contribution larger than your room floors "remaining room" at $0 while the percentage passes 100% — the over-contribution zone where CRA penalties start.

Worked example: $109,000 lifetime room, $20,000 contribution (2026)

Take someone who turned 18 before 2009, has been a Canadian resident every year since, and never contributed to a TFSA. Their 2026 lifetime room is $109,000. Planning a $20,000 contribution: remaining room = $109,000 - $20,000 = $89,000, and percentage used = $20,000 / $109,000 x 100 = 18.3%. The unused $89,000 carries forward — TFSA room never expires.

The cautionary version: available room $7,000, planned contribution $8,000. Remaining room = max($7,000 - $8,000, 0) = $0, and percentage used = 114.3%. That $1,000 excess attracts CRA's 1%-per-month penalty — $10 per month it stays in — until withdrawn. The tool cannot stop you entering it, but a percentage over 100% is your signal to shrink the contribution.

Practical tips

• Check your real room in CRA My Account first — institutions report contributions with a lag, so bank figures can be stale.
• Never recontribute a withdrawal in the same calendar year — room taken out only comes back the following January 1.
• Pace yourself: contributing monthly, aim for about 50% of room used by mid-year to avoid a December overshoot.