Does Ethereum halve like bitcoin?

No, Ethereum does not halve like bitcoin. There is no Ethereum halving built into the protocol. Instead, ETH issuance changes with the number of active validators, and a fee burn removes some ETH from circulation.

Is there an Ethereum halving?

Bitcoin's supply rule is fixed in its code. The Bitcoin Wiki explains that the block reward halves every 210,000 blocks, roughly every four years, which caps total supply just under 21 million coins. The guide to the bitcoin halving covers this in detail.

Ethereum never adopted that model. Its miners' block reward was cut by network upgrades rather than by a timer. EIP-649 set it to 3 ETH at the Byzantium upgrade, offsetting a delay to the so-called difficulty bomb. EIP-1234 lowered it to 2 ETH at Constantinople. These were one-off decisions made by the community, not scheduled events.

How does Ethereum issuance work today?

Since the Merge, Ethereum runs on proof of stake. Ethereum.org says issuance on the execution layer, where miners used to be paid, dropped to zero. New ETH now goes only to validators as rewards, and the site estimates total new issuance fell by about 88% compared with before the Merge.

How much is issued depends on participation. Ethereum.org's page on rewards explains that each validator's base reward is divided by the square root of all ETH staked. Ben Edgington's book on the protocol, Upgrading Ethereum, adds that total issuance therefore rises with the square root of the number of validators. More staking means more ETH issued overall, but a smaller reward for each validator. The book also notes that the main tuning constant, set at 64, has never changed.

In practice, issuance is also lower than the maximum when validators miss duties, because missed work earns no reward.

How does the EIP-1559 burn affect supply?

EIP-1559, introduced in August 2021, split fees into a base fee and a tip. The base fee is destroyed rather than paid to anyone, and the tip goes to the block producer. The base fee can move by up to one eighth per block depending on demand for block space.

This makes net supply a tug of war. Ethereum.org estimates that an average gas price of around 16 gwei would burn roughly as much ETH as validators earn each day. Busier periods can burn more than is issued, while quiet periods add to supply.

Is Ethereum deflationary because of this?

Only at times. A shrinking supply needs the burn to outpace issuance, and that depends on network activity, not on a fixed rule. The full history of when ETH supply grew or fell is covered in is Ethereum deflationary.

The key difference from bitcoin is predictability. Bitcoin's future issuance can be calculated years ahead. Ethereum's depends on staking levels and fee demand, and any change to the reward formula would need a network upgrade agreed by the community.