What was Bitcoin’s first block reward halving date?

Bitcoin’s first block reward halving occurred on 28 November 2012.

At that event, the subsidy paid to miners for adding a valid block fell from 50 bitcoins to 25 bitcoins. The reduction was built into Bitcoin’s protocol to control the rate at which new bitcoins enter circulation. It is commonly called a halving because the scheduled subsidy is cut by 50 percent.

The first halving took place at block 210,000, although the exact calendar date was not fixed in advance. Bitcoin’s block production varies slightly because mining difficulty adjusts periodically, so halving dates are usually estimated from block height rather than selected as calendar appointments.

Halvings occur approximately every 210,000 blocks. Later halvings took place in 2016, 2020, and 2024. The subsidy is separate from transaction fees, which miners may also collect, and it is not the same as a change to Bitcoin’s maximum supply.