If you're new to shipping bubble mailers through Canada Post, the pricing system can seem arbitrary until you understand the classification rules. The same bubble mailer can cost $2.15 or $9.00 to ship depending on whether it meets a few specific dimensional thresholds. Getting this right makes a meaningful difference for any seller doing volume.
How Canada Post Classifies Mail Pieces
Canada Post uses three main domestic categories that affect bubble mailer pricing:
Letter Mail
The cheapest option. To qualify, a piece must be:
- Length: 140–380mm (5.5–15 inches)
- Width: 90–270mm (3.5–10.6 inches)
- Thickness: no more than 5mm (0.5cm)
- Weight: up to 500g
Bubble mailers rarely qualify here — even a thin one with a single sticker inside will typically be over 5mm. This category is mainly for flat envelopes.
Oversized Letter / Flat
This is where many bubble mailers can land if you pack carefully:
- Length: up to 380mm
- Width: up to 270mm
- Thickness: up to 20mm (2cm)
- Weight: up to 500g
An oversized letter to an Ontario address costs roughly $2.45–3.75 depending on weight zone, compared to $9–14 for the equivalent parcel. This is where packing matters.
Parcel
Anything thicker than 20mm, heavier than 500g, or larger than the flat dimensions above ships as a parcel. Parcel rates start around $9–10 for local Ontario delivery and climb steeply for cross-country shipments ($14–22+). For something that could have shipped as an oversized letter, the cost difference is often $6–10 per package.
Approximate Canada Post Rates (2024–2025)
These are approximate retail rates. Venture One (free signup) provides a small discount. Rates change annually — verify at canadapost.ca before relying on specific numbers for pricing.
| Service Type | Max Thickness | Max Weight | Local/Ontario | Cross-Canada |
|---|---|---|---|---|
| Oversized Letter | 20mm (2cm) | 500g | ~$2.45–3.50 | ~$3.50–4.80 |
| Small Packet | No limit | 2kg | ~$9.00–12.00 | ~$11.00–18.00 |
| Parcel (Expedited) | No limit | 30kg | ~$9.50–14.00 | ~$12.00–22.00 |
| Priority | No limit | 30kg | ~$16.00+ | ~$22.00+ |
Dimensional Weight — What It Means
For parcels, Canada Post uses dimensional weight pricing when the calculated dimensional weight exceeds the actual weight. The formula is:
Dimensional weight (kg) = (L × W × H in cm) ÷ 5000
Example: a bubble mailer measuring 30cm × 22cm × 5cm has a dimensional weight of (30 × 22 × 5) ÷ 5000 = 0.66kg. If the actual item weighs 200g, Canada Post charges based on the 660g dimensional weight. This matters most for large but lightweight items (bulky clothing, foam items) and less for dense, small items.
For items staying under the 2cm threshold, dimensional weight doesn't apply to oversized letters — you're billed by actual weight only, up to 500g.
ChitChats vs Canada Post for Etsy Sellers
ChitChats is a third-party shipping service that routes Canadian packages through US entry points to access USPS commercial rates, then delivers via Canada Post for domestic legs. For Canadian sellers shipping to US customers — which describes most active Etsy sellers — the difference is significant.
A typical small parcel to a US address through Canada Post Small Packet USA Surface: approximately $10–14. The same package through ChitChats to a US address: approximately $5–8 depending on weight and destination zone. For sellers doing 30–50 US shipments per month, that's $150–300 in monthly savings.
For purely domestic Canadian shipments, ChitChats is less compelling — Canada Post Venture One rates are competitive, and ChitChats domestic pricing is comparable rather than dramatically cheaper. The advantage is primarily on US-bound packages.
Other considerations for ChitChats:
- You drop off at a ChitChats location or schedule pickup (locations in major Canadian cities; check their website for the nearest one)
- Labels are generated through their app; no Canada Post account needed for US shipments
- Tracking works through ChitChats' system, handed to USPS in the US, delivered by USPS
- Insurance and claims are handled through ChitChats, not Canada Post
See the retailer comparison and full size guide for more on choosing the right mailer to stay under the 2cm threshold.