Bitcoin Forum

I tried sending money using MultiBitHD - why are there two recipient addresses?

this is really stressing me out. I wanted money to go to one specific address, but when I click on payment details, two addresses show up, including the one I directed my money to!

Should I click 'undo transaction' before it's too late? Please advise me ASAP. Thanks

One is for the recipient of the coins you send, the other is your change address.


This is nothing to worry about, multibit HD discourages address reuse, which is perfectly fine for a wallet.

Bitcoin does not work with balances, but with whats called "inputs". If you have received a total of 1 BTC on an address, you can spend 1 BTC, but it matters how you received them. If you received 1 BTC in a single transaction you have 1 input worth 1 BTC (case A). IF you received the 1 BTC in 10 chunks of 0.1 BTC each, you have 10 inputs worth 0.1 BTC each (case B).

Lets assume you now want to spend 0.5 BTC (no fee for simplicity).

In case A you have a 1 BTC input, so you need to create two outputs (to be used later as inputs in another transaction). One worth 0.5 btc to the recipient and one 0.5 worth BTC back to yourself.

In case B you have 10 inputs worth 0.1 each, so you can just use 5 of them to create a single 0.5 BTC output. In this rare case there is no change. Usually however the inputs dont cleanly match the amount you want to send and thus there will be a change output. Multibit HD uses a new address whenever there is change. As its covered by the seed, the coins are still yours and you can spend them same as all other coins you received.