Pending, Unconfirmed, Mempool: how wallets show unconfirmed bitcoin

Three ways to show an unconfirmed transfer

1. On a separate line, not in the balance. The main balance doesn’t change until the transfer is confirmed, and a line such as “Pending”, “Mempool” or “+amount incoming” appears next to it. Judging by the source code, this is how Bitcoin Core, Sparrow, BlueWallet and Phoenix (for on-chain transfers) work. Code changes between versions, so check against your own app. This is the most cautious option, but it still shows the amount, and a scammer will say: “Look, it’s right there.”

2. In the total balance, with a label. The amount goes straight into the total balance, with a label next to it or inside it. Judging by its code, Electrum shows an “Unconfirmed” portion, and by default it lets you spend unconfirmed coins. According to its help pages, Exodus marks an unconfirmed transfer as “Pending”; it counts toward the wallet’s total balance but not the “available” one, and it can’t be spent before confirmation. Looking at the total balance in these wallets, it’s easy to assume the money has already arrived.

3. Only after confirmation. The amount appears in the balance once the transfer is in a block. According to its help pages, this is how bitcoin works in MetaMask. It’s harder to be misled here, but the transfer may still be visible in the history, and that can be used to pressure you.

Do wallets warn that a transfer can be cancelled?

Rarely, and not always. For example, judging by its code, Muun labels an incoming unconfirmed transfer “Cancelable” and warns that the sender can cancel it until it is confirmed. But it does this only for transfers flagged as replaceable, while today the network also allows replacing a transfer without that flag. In many wallets you will see only “Pending” or “Unconfirmed”. So the absence of a warning means nothing: only confirmation counts. Why this happens is explained in the article on how a sender takes back an unconfirmed transfer.

What happens when a transfer is replaced

It varies, and not always right away. In some wallets the replaced transaction simply disappears from the history along with the amount. In others it may stay on screen for a while. This happened in Ledger Live before version 2.7.0 (2020): the balance went up by the unconfirmed transfer and didn’t go back down after it was cancelled. The bug was fixed, but the case shows that a wallet’s screen can lag behind the network or get it wrong.

So in a disputed situation, check the transfer in a block explorer: it shows “Replaced” and a link to the transaction that took its place. Step by step in the article how to check a bitcoin transfer.

How to learn how your wallet behaves

1. Send yourself a small amount from another wallet or from an exchange.
2. Right after sending, look: has the main balance changed? Is there a “Pending” line or a label on the transaction?
3. Open the transaction and find where the number of confirmations is shown.
4. Wait for the first confirmation and see how the status changes.

A few minutes, and during a deal you will know exactly where to look.

What to do during a deal

1. Don’t look only at the balance.
2. Open the transaction itself and find the number of confirmations.
3. While it shows 0, assume the money hasn’t arrived yet.
4. If in doubt, copy the transaction hash (TXID) and check it in a block explorer.
5. If someone rushes you with “refresh, it’s already there”, that is almost always a bad sign.

What exchanges do

Major exchanges credit an on-chain bitcoin deposit after confirmations. According to their public help pages: Binance needs one confirmation to credit a deposit and two before it can be withdrawn; Kraken needs three confirmations (their estimate is about 45 minutes, but the time is not guaranteed). A bitcoin seller would do well to follow the same rule. Before a deal, check the buyer’s bitcoin address in GuardPay /check.