You aren't taxed on the estimated value of your bitcoin. If you bought bitcoin at $2 (for example) five years ago, and now it's worth $5000, you owe no taxes.

You aren't taxed on the estimated value of your bitcoin. If you bought bitcoin at $2 (for example) five years ago, and now it's worth $5000, you owe no taxes. However, if you sell the bitcoin for a gain of $4998 USD, now you owe tax on the $4998 you realized in gain. Unless, you sell your bitcoin and just spend all the money, you should be fine just keeping your money in bitcoin.