Fractal Bitcoin completes first halving, block reward cut to 6.25 FB

Fractal Bitcoin announced that its first scheduled halving was executed at block 2,100,000. The consensus upgrade FIP‑102 reduced the per‑block reward on the Fractal side from 25 FB to 6.25 FB and earmarked an additional 6.25 FB for future distribution on the Bitcoin mainnet.

How the reward structure changed

Before the upgrade each of the three mining mechanisms – Merged Mining, Permissionless Mining and Index Mining – received roughly 8.33 FB per three‑block cycle (25 FB total). After the halving each eligible block carries a 6.25 FB reward, which is split evenly across the three mechanisms (about 2.08 FB each). The second 6.25 FB per block is reserved for a Bitcoin‑mainnet distribution budget.

Future distribution on Bitcoin

FIP‑102 does not increase the total supply of FB. Instead it creates a parallel emission budget that will be released on Bitcoin through the upcoming FIP‑103 proposal. The rollout is planned to start in the fourth quarter of 2026, with a full implementation targeted for the first quarter of 2027.

Technical and operational notes

• Network nodes and indexing services reported normal operation during the first ten minutes after activation.
• The halving follows Bitcoin’s 50 % block‑subsidy reduction model, though Bitcoin’s current reward is 3.125 BTC per block.
• Fractal’s merged‑mining relationship with Bitcoin remains unchanged, leveraging SHA‑256 compatibility.

Next halving milestone

The next reward reduction for Fractal Bitcoin is scheduled for block 4,200,000, after which both the Fractal‑side and Bitcoin‑mainnet allocations are expected to halve again, unless a future improvement proposal modifies the schedule.