Approximately 20% of all mined BTC are now lost, but experts estimate that about 2.45% of them can be recovered. Lost Bitcoins still exist, but you just can’t get to them. They may be lost because of forgotten private keys or sent to the wrong address but the bottom line is, you probably won’t be having it back.
The case of the 2.45% is a much different story. One of the solutions to this issue is custodial wallets. Without having to turn over ownership of their keys, retail investors can hold their own private keys and still retain recourse through Crypto Asset Recovery in the event they lose their password to what they call “common crypto assets,” such as Bitcoin, Ethereum, Litecoin, Dogecoin or dozens of other altcoins.
The Crypto Asset Recovery website explains how it work: You provide us with a copy of your wallet (or even just your Wallet ID in the case of a Blockchain.info account) and your best guesses as to what your password is. We will use your password guesses to “brute force” your password. Bitcoin and altcoin passwords are secure enough to foil a brute force password attack when the attacker has no prior knowledge of the password. However, when the crypto asset owner knows part of their own password the probability of recovering it increases dramatically.”
The service asks for a percentage of BTC recovered. For instance, they may charge 20% for the first 10 BTC, and 15% for the next 10.
However, we all should remember that prevention is better than cure. Cryptocurrencies like BTC is worth a lot, so be vigilant about it so you won’t be facing any issues like this.