What happens when the last bitcoin is mined. The miners are used when transactions on the blockchain are put in and it completes when they are confirmed. But once the last amount is done (some have said as soon as 2037) what happens then?
The block reward will not drop to 0 until around 2140, but we will have mined 99.9% of all bitcoin by 2044, at which point the block reward will have fallen to less than 0.1 BTC from its current 6.25 BTC.
What happens is that over time, the fee being paid for transactions contributes more to the total mining reward and the block reward contributes less. The most recent block mined at time of writing, block 675,996, has a total mining reward of 6.98 BTC, of which 6.25 BTC is the block reward and 0.73 BTC is from fees.