Private Key Sweep vs. Import – A Beginner’s Guide
By: Ofir Beigel | Last updated: 1/22/23
Knowing the difference between importing and sweeping a private key is important, especially if you use paper wallets. In this post, I’ll explain the difference between the two methods and what to look out for.
Sweep vs. Import Summary
Sweep and Import are ways of transferring a private key onto a software wallet.
Import keeps the Bitcoins on the original private key, while Sweep sends the Bitcoins to a whole new private key connected to the software wallet. As a rule of thumb, sweeping is more recommended than importing.
That’s sweep vs. import in a nutshell. For a more detailed guide keep on reading, here’s what I’ll cover:
1. Importing a Private key
When you import a private key, you’re simply adding it to the collection of private keys in your software wallet.
If any bitcoins belong to the private key, they’ll now be included in your software wallet’s balance and remain assigned to that private key.
For instance, if you are importing a private key from a paper wallet, its bitcoins are now accessible via both the paper wallet and the software wallet. If anyone else gets their hands on that paper wallet, or have already had access to its private key, they can still spend its bitcoins.
Additionally, any bitcoins sent to the paper wallet in the future will be credited to both the paper wallet and the software wallet.
Another important thing to keep in mind is that once any of the private key’s bitcoins are spent using the software wallet, the private key will be completely depleted of its bitcoins – Even if only a portion of its bitcoins are spent!
This is because Bitcoin transactions spend the entire balance of a private key, and send any leftover change to a newly generated private key in the software wallet.
For other issues that can occur when importing a private key, read this post.
When Should You Import a Private Key?
You should only do an import if you generated the private key (or paper wallet) yourself and no one else has ever, or will ever, have access to it. If someone else gave you the paper wallet, or its private key has been seen, you should sweep it instead.
2. Sweeping a Private Key
Sweeping a private key is the same as importing it, but with an extra step – all of the bitcoins belonging to the private key are sent to a new Bitcoin address on your software client.
This is done via a Bitcoin transaction, so an internet connection is required to send out the transaction and complete the sweep.
After the sweep is complete, the original private key will be completely depleted of funds and all of its bitcoins will belong to a new private key in the software wallet.
Since sweeping involves sending a transaction (to yourself), a miner fee will be deducted from your balance.
When Should You Sweep a Private Key?
You should sweep a private key if someone else had access to the private key (e.g. if someone gave you a paper wallet or the private key was published online).
This will prevent a potential hacker from ever being able to spend the bitcoins associated with it.
As a rule of thumb, if you’re in doubt of whether to import or sweep a private key, you should probably sweep it. Sweeping solves many of the issues that can arise from doing an import.
3. Import and Sweep Support
Here’s a short list of Bitcoin wallets that have the built-in capability to import and/or sweep a private key:
4. Conclusion
Both Sweep and Import are valid methods for transferring a private key into a software wallet. Sweep seems to be the safer way to go, although you will need an internet connection and it will cost you a miner fee. A small price to pay for some peace of mind.
Have you imported or swept a paper wallet in the past? I’d love to hear about it in the comment section below.
Can you sweep crypto from one paper wallet to another paper wallet? What are the costs?
Great Question JH!
Yes, it is possible to sweep crypto from one paper wallet to another paper wallet. To do this, you will need to import the private key of the original paper wallet into a software or hardware wallet that supports the crypto you are trying to sweep. Once the private key is imported, you can then send the crypto to the address of the new paper wallet.
The cost of sweeping crypto from one paper wallet to another will depend on the network fees of the blockchain that the crypto is on. For example, if you are sweeping Bitcoin, you will need to pay a network fee to the miners who process the transaction on the Bitcoin blockchain. These fees can vary depending on the current demand on the blockchain, but you can use a fee estimator tool to get an idea of how much you will need to pay.
It’s important to note that sweeping crypto from one paper wallet to another involves moving the private key from one place to another, which can be risky. If the private key is lost or stolen, the crypto it controls can be lost permanently. Therefore, it’s essential to take the necessary precautions to ensure the security of the private key during the process.
Pls include other currencies too. all material online is about BTC… and fairly easy to do . not so with other currencies.
then swap whatever u have to BTC first… u can swap it back later on…
Sweeping the entire balance can be expensive (and slow) when moving from a very old wallet to a modern one (and a “small” amount then would mean a huge amount by now). An alternative way of doing so is to first import it, then immediately send a small amount from the new wallet to another wallet (e.g. an exchange). Then the original private key will be depleted and all your coins will be moved to a freshly generated private key, without having to pay the miner fee.
So what if I hold my paper wallet and no one else, and I destroy it after I importing. Is it still unsafe to import? could this lead to problems too?
so what if you can’t remember which set of 12 words were for legacy p2pkh bitcoin address. Nor can you remember where the wallet came from? I do have the wallet id tho and the receipt from the deposit. Also will the original addresss have the balance on the blockchain even after the sweep?
I want to transfer out my BTC from paper wallet , to my Trezor wallet, how can I ? Thank you very much !
Can I sweep the private keys when I move them from Coinbase to Ledger Nano X?
Neither of them give you the private keys, fyi.
This is true to an extent. While Coinbase and Ledger act as a custodian of your keys, the wallets still require a public/private key set to send and receive coins. Who has control over those keys is a whole different story. If you don’t own the keys, you don’t own the crypto
There would be no need to sweep since you would be making a transaction, sending coins from a Coinbase wallet to a ledger wallet, in order to transfer the coins. By performing the transfer the coins are “assigned” to the keys of the destination Ledger wallet and this is recorded in the blockchain (public ledger). There would be no way for the Coinbase wallet keys to spend the coins that have now been assigned to the new Ledger wallet keys . Such action would be “double spending” which is prevented by the blockchain. Sweeping is essentially sending coins from a wallet, with private key A, to the same wallet, with new private key B. By performing a transaction you cut off all ties to the keys from which the coins came and assign a new set of keys. One would sweep if they believed someone may have access to their private key. Importing a private key only copies the wallet with the same key set as before usually to restore a lost or corrupted wallet.
so what if you can’t remember which set of 12 words were for legacy p2pkh bitcoin address. Nor can you remember where the wallet came from? I do have the wallet id tho and the receipt from the deposit
This is a difficult one to answer. It is not unlikely for crypto assets to get lost to time because someone forgets his or her password. If you cannot remember but you have all the other info, try getting in touch with a customer service rep. Tell them the information you have and they might be able to ask you probing questions that ultimately lead you to remembering the login information. Once you have that, it would be a good idea to make a record of it somewhere.