Knowledgebase: Bitcoin
I overpaid or underpaid on a Bitcoin transaction!
Posted by zz Werner vR on 21 Jul 2014 16:31

There are only two things that you need to complete a Bitcoin payment: a wallet address and a BTC amount. 

Both of these will be displayed to the buyer on the PayFast engine page during checkout.

If you, as buyer, made an underpayment you'll be prompted to top up the remaining Bitcoin amount for the payment to clear to the seller. 

If you overpaid for the transaction, your payment to the seller will clear (and they can start delivering your items), but the extra bitcoin change amount will need to be sent back to your wallet.

To do this you need to:

  1. Go to
  2. Click Register if you don't have a PayFast account.
  3. Enter your name, email address used for the transaction and select a password. You don't have to tick the checkbox that allows you to receive payments (unless you want to sell with PayFast, that is). 
  4. Verify your email address (this is to prevent unauthorised access to your account and transaction history)
  5. Log in to your PayFast account

Logged in and on the PayFast Dashboard, you'll see a notification about your recent overpayment. You'll be able to enter a receiving wallet address, where the change amount should be sent. The receiving wallet should receive the change amount within an hour.

Note that we can't automatically send the change amount back to the sending wallet, since not all sending wallets can necessarily receive funds.