diff --git a/bitcoin/tx.c b/bitcoin/tx.c
index c48d255fa..61abb53c2 100644
--- a/bitcoin/tx.c
+++ b/bitcoin/tx.c
@@ -299,6 +299,7 @@ void bitcoin_tx_output_set_amount(struct bitcoin_tx *tx, int outnum,
 	} else {
 		output->satoshi = satoshis;
 	}
+	wally_psbt_output_set_amount(&tx->psbt->outputs[outnum], satoshis);
 }
 
 const u8 *wally_tx_output_get_script(const tal_t *ctx,