What Happens to Unconfirmed Bitcoin Transactions?

Romj Amon
Romj Amon

Updated · Oct 16, 2022

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A confirmed Bitcoin transaction is one that is part of the blockchain. Conversely, an unconfirmed is one that’s still pending.

Every confirmation represents a block. The consensus is that it generally takes 3–6 confirmations to deem a blockchain record irreversible.

For large trades, especially those worth millions of dollars, recipients may want to see dozens of confirmations.

The problem is that Bitcoin has scalability issues. And miners don’t pick transactions on a first-come, first-served basis. That’s why many don’t get confirmed as expected.

Keep reading to know what happens to unconfirmed Bitcoin transactions and what you can do about them.

Why Is My Bitcoin Transaction Unconfirmed?

Recency, mempool congestion, and network fee amount could explain why your BTC transaction isn’t confirmed. 

  • Recency - Bitcoin transactions don’t get confirmed instantly. About 10 minutes is the fastest time to get a confirmation, for it’s how long a miner finds a block. Therefore, the typical waiting period is half an hour.

That said, newer trades could get fully confirmed more quickly than older ones.

Why?

Keep reading.

  • Mempool Congestion - Short for memory pool, a mempool is where a blockchain unconfirmed transaction stays. Each node, a computer that executes Bitcoin, maintains one. Every winning miner goes here to choose transactions when filling up a block.

Till now, each block can store a maximum of only 1 MB of data or more than 2,000 transactions. In addition, Bitcoin can process seven transactions per second only.

If the volume exceeds the network’s capacity, some pending transactions remain in limbo longer.

  • Network Fee Amount - Mempool congestion can drive up network fees. Since miners are profit-driven, they scoop up trades that generate the most revenue.

Therefore, the unconfirmed Bitcoin transactions whose senders pay the highest fees take priority.

Unfortunately, not all crypto wallet providers let you set or pick a fee. Even worse, some vendors provide no recourse to move your transaction higher in the mempool.

If the network fee is small and unchangeable, you can’t do anything to make it more enticing. Unless the mempool decongests, your transaction may not be included in a block soon.

What Happens to Unconfirmed Bitcoin Transactions

Pending transactions will be stuck in the mempool indefinitely until they get confirmed. They could stay in this virtual waiting room for weeks. But their status won’t be “unconfirmed” forever. 

Eventually, pending trades will disappear from the mempool as if nothing happened. Nodes like to play favorites when too many BTC senders bid fees higher than the threshold. To make room for more high-value transactions, they would remove the low-value ones.

Mind you, all miners have to wipe their memory of your unconfirmed transaction first before the network considers it forgotten. Otherwise, it would still be pending in the mempool of the nodes that didn’t remove it.

Reverse a Transaction

If your Bitcoin transaction is not confirming, there are four fee-bumping methods to fix it, as follows:

1. Replace by Fee (RBF) - Some BTC wallets let you resend the funds with a higher network fee. Paying more money is often enough to persuade miners to prioritize your unconfirmed transaction.

With RBF, the new transaction replaces the original one. There are different types of it, and some nodes don’t support specific variants.

Delayed RBF is one example that permits transaction replacement only after a certain number of blocks has passed.

2. Double Spending - Unlike RBF, this option isn’t going to rebroadcast the same Bitcoin transaction. Rather, it involves creating a separate transaction with the same amount and a higher fee. The difference is that the new transfer attempt doesn’t override the original.

Upon receiving confirmation, the second transaction can invalidate the first one. For this reason, the same BTC doesn’t get spent twice. So, double spending doesn’t really occur, despite its name.

3. Child Pays for Parent (CPFP) - It allows the receiver to pay an additional fee to help move up an unconfirmed blockchain transaction in the mempool. 

It involves broadcasting a new transaction (child) with a higher fee, which spends an unconfirmed output of the original transaction (parent).

The parent trade must appear before the child on the blockchain. So, the miner has extra motivation to include the former in a block to pocket the latter’s high fee.

4. Transaction Acceleration - Some mining pools accept extra payment from low-fee unconfirmed transaction senders.

It involves sending the funds directly to the miner that permanently records your trade on Bitcoin’s ledger. So, the exchange won’t appear on the blockchain at all.

Cancel a Transaction

Using RBF to reverse BTC unconfirmed transactions effectively cancels the original ones with lower fees.

If you take the double spending route, make sure that you’re the coin recipient the second time around. This way, the money will go back to your BTC wallet when the new transaction confirms.

If you use a Bitcoin exchange, you may be able to undo a Bitcoin withdrawal request to an external address.

Stopping BTC withdrawal requests can be easier and cheaper than canceling blockchain pending transactions. A withdrawal request that’s in progress means that no trade was broadcasted to the Bitcoin network.

How To Ensure Confirmation

To spare yourself the anxiety of not knowing when your unconfirmed blockchain transaction will push through, consider these tips:

Check Whether You Can Set Fees

First and foremost, find out if you have control over network fees.

Some crypto wallet vendors dictate the fee. They can unilaterally finalize the amount even when they let you classify your transaction as low, medium, or high-priority.

And then there are wallet providers that give you more latitude in deciding how much you pay. They may permit you to set a custom amount, which is convenient and risky.

Having the power to set network fees can be neat, but it can also backfire on you. If you don’t know how low is too low, you may pay too little.

When taking this route, do your homework to learn what fees Bitcoin miners are likely to ignore. This way, you can set a reasonable amount without overpaying.

See How Congested the Mempool Is

Be aware of the mempool size before sending funds. It can single-handedly leave your blockchain transaction unconfirmed for hours.

Google can reveal the most reliable sites that provide this information. These can also give you fee suggestions to help your trade get noticed.

High mempool congestion means a deluge of transaction volumes. Given Bitcoin’s technical limitations, only those who pay top dollar can grab the interest of miners.

If you’re not in a hurry to send BTC, wait it out.

Sooner or later, the number of incoming transactions will go down. And when it does, low fees will be the norm. In turn, the miners can’t be too greedy and will include low-value blockchain unconfirmed transactions.

But if you must move the funds quickly, you may have to bite the bullet and pay above average. It’s the only way to put your transaction front and center when the network is busy.

Explore the Transaction Reversal Options Your Wallet Supports

As mentioned, not all crypto wallets can accelerate the confirmation of pending Bitcoin transactions. So before depositing lots of funds to one, understand what it can do for you if your trade gets stuck.

If your wallet supports RBF, make the network fee “replaceable” before initiating a transaction. This way, you’ll be able to set a higher price if the network ignores it longer than you can tolerate.

Move Funds to Internal Wallet Addresses

Avoid Bitcoin unconfirmed transactions altogether by moving funds between custodial crypto wallets controlled by one broker.

Sending BTC to an external wallet is a withdrawal. It would involve the Bitcoin network and incidentally prompt an on-chain transaction. By definition, there’s a risk that it would stay unconfirmed indefinitely.

But if you transfer the coin to a fellow platform user, the miners will be out of the picture. So, there’s no network fee. And the trade doesn’t have to sit in the mempool either.

As a result, the BTC may appear in the destination wallet in real-time without any extra charge.

Such a transaction may not be an official blockchain record, but it gets the job done. Plus, it’s still verifiable through your wallet vendor’s private ledger.

Broadcast Off-Chain Transactions

Don’t directly use the main Bitcoin network to keep your Bitcoin transaction from getting stuck as unconfirmed.

Instead, use Layer two chains and sidechains when sending small amounts of BTC. They may not have any confirmation requirement, so there’s no delay.

Layer 2 chains and sidechains are independent blockchains designed to help scale Layer 1 cryptos like Bitcoin. They have key differences, but both exist to speed up transactions and minimize fees.

As a medium of exchange, BTC is currently inefficient because these auxiliary chains haven’t yet gone entirely mainstream. They may, though, become ubiquitous soon. 

In fact, Lightning Network, the most popular Bitcoin Layer 2 solution, has gone live on Cash App and Robinhood. That’s why users of both platforms can now do BTC transactions fast and at a fraction of the cost.

Wrap Up

The time-consuming process of getting BTC transactions processed is a necessary sacrifice to prevent double spending. But not knowing exactly how long for a Bitcoin confirmation can be unnerving, especially when crypto prices are wildly volatile.

Fortunately, there are ways to reverse and cancel pending BTC transfers. And with the advent of Layer 2 chains and sidechains, the days of inefficient crypto trades are numbered.

Until off-chain transactions become the standard, always exercise due diligence to avoid the hassles of getting ignored by the network.

FAQ.


Why is my Bitcoin transaction pending for so long?

There are three explanations for this:

  • Your transaction is less than 10 minutes old.
  • The Bitcoin network is handling a high volume of trades.
  • The fee you priced was too low to convince winning miners to prioritize your trade.

Will an unconfirmed Bitcoin transaction be returned?

Unless it gets confirmed, it will disappear from the queue once all nodes remove it from their mempools.

Your Bitcoin transaction could stay unconfirmed for days or weeks before the network completely forgets about it.

Once forgotten, your BTC would be again accessible for spending.

Can I cancel an unconfirmed Bitcoin transaction on the blockchain?

But your cancellation options depend on the wallet you use.

The most common way to cancel a pending BTC transfer is through Replace by Fee or double spending.

The former involves rebroadcasting the transaction, except the fee is higher. In comparison, the latter is about creating a separate identical transaction of the same amount. You need to include a higher miner fee and send the funds to yourself.

If you withdraw BTC from a custodial wallet to an external address, you may be able to cancel it. As long as it’s still in progress, you can stop it from getting broadcasted to the Bitcoin network.

Can you spend unconfirmed transactions?

No, you can’t.

While waiting for confirmation, your pending on-chain BTC transaction puts the coin on hold.

The unspent funds will return to your wallet only after the whole network removes all traces of your unconfirmed transaction. And to get your BTC back more quickly, you can cancel it through double spending.

Read the above article to understand what happens to unconfirmed Bitcoin transactions entirely.

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Romj Amon

Romj Amon

Romj is a veteran copywriter who used to be a Jack of all trades. Now, he's trying to be a master of one: technology. He jumps down the rabbit hole to size the latest innovations up. As a content contributor for TechJury, he hopes to help you keep up in our fast-paced world with his discoveries.

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