Zcash has cut its block time before, and the reward went with it

The Zcash NU7 upgrade activated on the public testnet at block 4,465,026, mined on 4 October at 18:21:45 UTC. The Zcash Foundation's release of 2 October had put activation at 6 October, so the chain reached it about thirty-six hours early. Target block spacing drops from 75 seconds to 25. Developers decide on mainnet activation on 20 October, fifteen days from now, and are aiming at 5 November.

“NU7 brings blocks every 25 seconds instead of every 75, a new Network Sustainability Mechanism that recycles part of every transaction fee into future block rewards, and new shielded limits that protect wallets from spam.”

— Zcash Foundation, 2 октября 2026

The speed number is the second one

Zcash did this in December 2019. Blossom activated at block 653,600 on 11 December, cut target spacing from 150 seconds to 75, and halved the per-block reward so that emission per unit of time stayed where it was. NU7 runs the same arithmetic with a three instead of a two: blocks arrive three times as often, the per-block reward falls to a third, and the issuance schedule and halving dates do not move.

In daily terms Zcash goes from 1,152 blocks to 3,456. A first confirmation averages 25 seconds instead of 75. Against Bitcoin's ten-minute target that is twenty-four times faster.

Sixty per cent of every fee leaves circulation

ZIP 235 takes 60% of every block's transaction fees out of circulation and puts them in a reserve. Miners keep 40%. ZIP 237 then pays a small predictable slice of that reserve back out on top of each block's normal reward.

Ethereum's EIP-1559 destroys the base fee and it never returns. Zcash sends the fee out of circulation into the reserve and pays it back later. Zcash is capped at 21 million coins, the last of which arrive around 2032, and after that miners live on fees alone. The reserve is built against that date.

Sprout, the original shielded pool from 2016, stops accepting new JoinSplits under the same upgrade.

The asset this ships on

ZEC trades at $1,322, a market capitalisation of $22.4bn and tenth place by size. The price is up 715% over twelve months, and the sector it belongs to has been making highs while the rest of the market did not. When Blossom shipped in December 2019, ZEC was a sub-$1bn asset outside the top thirty.

$1,322 is 58.6% below the $3,192 of 28 October 2016, Zcash's launch week. Only a few thousand coins existed then. There are 16.97 million now.

On testnet the blocks arrive on schedule. On 20 October the developers find out whether that holds with real hashrate pointed at the chain, and the testnet run is the only evidence they will have.

Informational material, not investment advice. Mainnet activation is a decision the developers have not taken yet.