The core difference: public vs private
Bitcoin and Monero are both accepted on CryptoPostage, but they work very differently at the network level. Bitcoin transactions are publicly visible on the blockchain. Anyone can see that a given address sent a specific amount to another address at a specific time — though they may not know who owns those addresses. Monero transactions are private by default. The sender, recipient, and amount are all hidden using ring signatures, stealth addresses, and RingCT. There is no public transaction record to inspect.
Confirmation times
Bitcoin requires one on-chain confirmation for label generation, which takes 10–20 minutes at standard fees. Monero requires 10 confirmations — each block is approximately 2 minutes, so expect 20–30 minutes. Bitcoin is faster for individual labels; the difference is small in practice. For bulk shipments where you're waiting anyway, the extra Monero time is negligible.
Wallet options
Bitcoin has a broader wallet ecosystem: Ledger, Trezor, Coldcard, Sparrow, BlueWallet, Electrum, and most major exchanges support on-chain BTC withdrawals. Monero wallets include Feather Wallet (recommended for desktop), the official Monero GUI, Cake Wallet (mobile), and Monerujo (Android). Hardware wallet support for XMR is more limited — Ledger supports Monero but requires extra steps.
Privacy at the payment level
If you pay with Bitcoin, a blockchain analyst can potentially see that a given BTC address paid a certain amount at a certain time. With some additional information, they could connect that to your shipping identity. With Monero, there is no public transaction record. Even CryptoPostage's payment processor cannot determine your wallet address from an XMR integrated address after the fact.
Which should you choose?
Use Bitcoin if you want faster confirmation, more wallet options, or you don't have a strong privacy preference. Use Monero if financial privacy matters — you don't want a transaction record connecting a payment to a shipping service to exist on any public ledger. For everyday shipping where privacy isn't a concern, Bitcoin is the simpler choice. For sensitive shipments or users with strong privacy needs, Monero is the correct tool.