As of January, 13, 2018, 80% of all Bitcoins that will ever exist have been mined. The next halving is a little over two years away, at which point inflation will fall to 2%.
The “halving” occurring with block 6,930,000 would then push the reward below 1 satoshi, thus no block reward would be paid out anymore.
You can find a table with the respective calculations here: Bitcoin Reward Schedule
Really, the mining reward might be too little to pay for mining efforts much earlier: already in 2036 99% of the bitcoins will be in circulation, in 2048 it will be 99.9%.