Canada Post stamp calculator
Find the postage rate for any letter by weight and destination, then work out the cheapest combination of stamps to pay it.
Pick where it's going and how heavy it is. Prices are Canada Post consumer rates and exclude tax.
Where the letter is going.
Canada
USA
International
Most mail is a standard envelope. Heavier or oversized items are priced as a large envelope.
Envelope
Standard letter or card
Large envelope
Oversized or thick mail
In grams.
Envelope (Standard Lettermail)
Based on the Permanent™ stamp rate, sold in booklets, coils and panes. A single stamp bought at the post office counter is $1.44.
Price excludes tax and is subject to change without notice.
Tell us which stamps you have. We'll find the cheapest way to cover the postage without overpaying.
Using the postage above — type to override.
Tick the stamps you already own.
Have a different denomination? Add it here.
Not sure how much your letter weighs? Estimate it from your envelope and pages first.
Rates shown are the published Canada Post consumer prices for Lettermail and Letter-post, effective January 13, 2025, and exclude taxes. Prices can change at any time without notice and are provided for general guidance without guarantee — always confirm the current price on the official Canada Post price list before mailing.
Skip the stamps. Send it online.
No trip to the post office, no weighing, no guessing the postage. Upload your PDF and we'll print, envelope, and mail your letter across Canada or abroad.
“Online-Post makes sending mail completely effortless. I've been using the service for months, and the recent enhancements to their interface and features have made it even more user-friendly and efficient. It is a highly convenient solution and a fantastic alternative for anyone wanting to bypass regular trips to a Canada Post office.”
SR
June 2026
Understanding Canada Post stamps and letter rates
A few things worth knowing before you buy stamps or drop a letter in the mailbox.
What is a Permanent™ stamp?
A Permanent™ stamp shows the letter P in place of a price. It always pays for a standard letter mailed within Canada (up to 30 g), no matter when you bought it. If rates go up, your older Permanent stamps still cover a regular letter, with no top-up needed. Bought in a booklet, coil, or pane, a Permanent stamp costs $1.24 today.
Any stamp can pay for any destination
A stamp is simply prepaid postage value. Canada Post accepts any mix of stamps as long as their combined value covers the price. You can overpay, but never underpay. So a USA or International stamp works on a letter within Canada, and Permanent stamps can go toward overseas mail.
The Permanent stamp is the one exception to fixed value: it always counts as the current domestic rate (currently: $1.24). The calculator above picks the combination with the least overpay.
Envelope vs. large envelope sizes
Size matters as much as weight. A standard envelope has to stay within both a size and a 50 g limit: go over either one and it is priced as a large (oversize) envelope, from $2.61. The calculator makes this switch for you when you enter a standard envelope over 50 g. You can't go above 500g with letter rates. For these you need to use a parcel service.
Standard envelope
- Max size
- 245 x 156 x 5 mm
Large envelope
- Max size
- 380 x 270 x 20 mm
Both must measure at least 140 × 90 mm. Sizes are length × width × thickness.