Written by Gregory Gosson
Have you sent someone bitcoin, but they’re yet to receive it? Are you waiting to receive some yourself, but the transaction just says it’s pending?
As more and more people wake up to the usefulness of Bitcoin, more and more people are going to beclogging upthe network. Here’s why your Bitcoin transaction could be stuck and how to avoid it.
How Do Bitcoin Transactions Work?
Whenever someone makes atransactionon the Bitcoin network, it’s broadcast to all the nodes.
Thenodes keep a fullrecord of the entire blockchain, as well as a collection of all the transactions yet to be confirmed in a block and added to the blockchain.
This collection of unconfirmed transactions isknown as the mempool.
Technically, each node has its own mempool, as well as each miner.
Minersuse the mempool to prioritize which transactions they want to include in the next block, assuming they win the chance to propose the next block by finding the correct hash during the mining process.
If your transaction is stuck on “pending,” it’s because it hasn’t been included in any of the blocks mined so far.
This is probably because miners are prioritizing other transactions to include in the next blocks they will add to the blockchain.
How Do Miners Prioritize Transactions?
Miners aren’t charities; they’re businesses. They need to make money.
Besides earning the block reward (currently 6.25 BTC), miners want to maximize their revenue.
They do this by giving priority to the transactions that pay the highest fees.
If the mempool is full of unconfirmed transactions, then the block space will be full and not all pending transactions will make it into the next block.
If the number of transactions added to the mempool grows faster than what the blockchain can handle, the number of pending transactions will grow.
Miners choose to include the transactions with the highest fees. These fees are voluntary and aren’t necessarily correlated to the size of the transaction.
Someone transferring just a few sats could choose to pay a higher miner fee than someone transferring several bitcoin.
Paying the minimum miner fee will mean your transaction will always be at the back of the queue.
This means your transaction will get stuck as “pending” until the number of unconfirmed transactions in the mempool shrinks or your fee becomes high enough relative to the fees of other unconfirmed transactions for miners to prioritize. If new transactions pay higher fees than you,your transaction could get stuck pending indefinitely, as it will constantly get moved to the back of the line.
How Long Do Stuck Transactions Stay Pending?
There is no definitive time for how long a stuck transaction will remain pending.
The mempool has amaximum size limitof 300MB. If the mempool fills to this limit, nodes will “forget” transactions with the lowest fees.
In this case, it will be like the transaction was never broadcast. Your funds return to yourwallet, and you can try sending the transaction again.
Even if the mempool never fills up, your transaction can be rejected and bounce back if it takes too long to be included in a block.
This is because nodes won’t hold transactions in their mempools for more than a few days. The exact amount of time varies, and your transaction may be stuck pending for some time before either being included in a block and confirmed or rejected.
How To Make Sure Your Transactions Are Always Confirmed
There is one definite way to make sure your transactions never get stuck pending and even ensure that they always get chosen to be included in the next block.
Pay higher miner fees.
The minimum fee is based on how congested the Bitcoin network currently is and how much space your transaction will take up on the blockchain.
If you have an urgent transaction to make, you have to be the highest bidder on the fee market. A general rule of thumb is to pay priority fees or higher to ensure your transaction will make it into the next block and be confirmed quickly.
Remember, if you’re paying a higher fee than anyone else, your transaction will always be included in the next block.
Most modernBitcoinwallets will automatically calculate the cost for the fees and give you options for economic and priority fees. There are also ways toanalyze the mempoolto work out the best fee to balance between keeping your costs down and getting your transaction confirmed.
You don’t have to pay the highest fee — just high enough that you aren’t constantly at the back of the line.
If the mempool is empty enough that the next block won’t be full anyway, feel free to pay the minimum fee.
But as more people start using bitcoin and more transactions get proposed, the competition to get included in the next block will only increase.If you want your transactions to be confirmed instead of getting stuck pending, you’ll want to familiarize yourself with the mempool and how to use it to determine what fees you should be paying.
How To Avoid Stuck Bitcoin Transactions
There are only three options to avoid stuck Bitcoin transactions.
Option 1 – Wait
The first one is not to avoid it and just accept it. If you are not in a hurry and don’t want to pay high fees, you can simply wait. Your money is safe, and if your transaction is not confirmed, it will bounce and be returned to your wallet. Using minimum fees is a great option if you have the time and want an economical way to send your money.
Option 2 – Pay higher fees
The second option is to adjust to the fee market and pay higher fees. If the network is congested, only the highest-paying transactions will be added in the next block. If you are willing to pay high fees, this will ensure your transaction is confirmed in a timely manner.
Option 3 – Use the Lightning Network
TheLightning networkis a second-layer payment network on top of Bitcoin that allows for instant and cheap transactions. You will need to pay blockchain fees to open and close a Lightning channel, but once it’s opened you can transact for very low fees.Take a look at all the custodial and non-custodial Lightning wallets.
Pro Tips:
–It’s smart to manage your Lightning liquidity during times of low fees.
–It’s smart to manage your UTXO sets during times of low fees.
As an expert with a comprehensive understanding of the intricacies of Bitcoin transactions, I can provide valuable insights into the concepts discussed in the article written by Gregory Gosson. My expertise in blockchain technology and cryptocurrency enables me to elucidate the factors influencing the speed and success of Bitcoin transactions. Let's delve into the key concepts outlined in the article:
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Bitcoin Transaction Process:
- Transactions on the Bitcoin network are broadcast to all nodes.
- Nodes maintain a full record of the blockchain and a collection of unconfirmed transactions called the mempool.
- Miners use the mempool to prioritize transactions for inclusion in the next block.
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Miners and Transaction Prioritization:
- Miners, as profit-driven entities, prioritize transactions based on the fees attached to them.
- The block space is limited, and transactions with higher fees are more likely to be included in the next block.
- Fees are voluntary and not necessarily proportional to the transaction size.
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Stuck Transactions and Mempool Dynamics:
- If a transaction is stuck on "pending," it means it hasn't been included in any mined blocks.
- The mempool can become congested, causing an increase in the number of pending transactions.
- Miners select transactions with higher fees, leaving lower-fee transactions pending.
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Duration of Stuck Transactions:
- The duration of a stuck transaction is uncertain.
- If the mempool reaches its maximum size limit (300MB), low-fee transactions may be forgotten, returning funds to the sender.
- Nodes may reject transactions that take too long to be included in a block.
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Ensuring Transaction Confirmation:
- Paying higher miner fees is the surest way to prevent stuck transactions.
- The minimum fee is influenced by network congestion and transaction size.
- Urgent transactions may require paying priority fees to ensure prompt confirmation.
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Adapting to Increasing Network Usage:
- As more people adopt Bitcoin, competition for block space will rise.
- Users should be aware of the mempool and analyze it to determine appropriate fees for transaction confirmation.
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Options to Avoid Stuck Transactions:
- Waiting for the transaction to be confirmed is an option, especially if time is not a critical factor.
- Paying higher fees adapts to the competitive fee market for quicker confirmation.
- Utilizing the Lightning Network, a second-layer solution, allows for instant and cost-effective transactions.
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Lightning Network:
- Lightning Network operates as a second-layer payment network on top of Bitcoin.
- It facilitates instant and low-cost transactions, requiring blockchain fees only for opening and closing channels.
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Pro Tips for Bitcoin Users:
- Manage Lightning liquidity during low-fee periods.
- Manage UTXO (Unspent Transaction Output) sets during times of low fees.
This comprehensive overview should equip individuals with the knowledge needed to navigate Bitcoin transactions efficiently, understanding the dynamics of the mempool and fee market to ensure successful and timely confirmations.
