--- title: "Solana activates Alpenglow consensus upgrade on mainnet" description: "Solana validators retired TowerBFT and activated the Alpenglow consensus protocol at slot 459,653,000, core engineering team Anza said, according to Decrypt. Anza said finality time drops from about 12.8 seconds to roughly 150 milliseconds. Anza CEO Brennan Watt called it the largest and most…" language: en canonical: "https://whycoinmoves.com/en/events/solana-solana-s-alpenglow-its-biggest-3d4c4e70e1bc54" published: 2026-10-21T04:38:04.000Z updated: 2026-10-21T14:29:01.000Z indexable: true --- # Solana activates Alpenglow consensus upgrade on mainnet Solana validators retired TowerBFT and activated the Alpenglow consensus protocol at slot 459,653,000, core engineering team Anza said, according to Decrypt. Anza said finality time drops from about 12.8 seconds to roughly 150 milliseconds. Anza CEO Brennan Watt called it the largest and most… Attributed sources: [CoinDesk](), [Cointelegraph](), [Decrypt]() ## Key facts Solana validators retired TowerBFT and activated the Alpenglow consensus protocol at slot 459,653,000, core engineering team Anza said, according to Decrypt. Anza said finality time drops from about 12.8 seconds to roughly 150 milliseconds. Anza CEO Brennan Watt called it the largest and most ambitious blockchain upgrade since Ethereum's Merge. Cointelegraph reported the upgrade targets a 99% reduction in finality time. Evidence strength: Multiple publishers, 3 publisher group(s) (CoinDesk, Cointelegraph, Decrypt); this describes source coverage, not truth or causation. After site detection, observed returns were 5 minutes: -0.14% (difference from BTC -0.04 pp; 21/10/2026, 04:38 → 21/10/2026, 04:43, UTC; Gate · USDT); 1 hour: +0.09% (difference from BTC +0.09 pp; 21/10/2026, 04:38 → 21/10/2026, 05:38, UTC; Gate · USDT). Unlisted windows are unavailable. In the preceding 30 days, the 99th percentile of absolute hourly returns was 2.05% (OKX · USDT; cutoff 21/10/2026, 04:38, UTC). This hourly baseline is not directly comparable with a minute move. ## Returns after site detection | Window | Return | BTC | Difference from BTC | Actual sampled interval (UTC) | Source | | --- | --- | --- | --- | --- | --- | | 5 minutes | -0.14% | -0.10% | -0.04 pp | 21/10/2026, 04:38 → 21/10/2026, 04:43 | Gate · USDT | | 1 hour | +0.09% | +0.01% | +0.09 pp | 21/10/2026, 04:38 → 21/10/2026, 05:38 | Gate · USDT | | 24 hours | — | — | — | — | — | ## Historical hourly baseline | Metric | Value | | --- | --- | | Ready | true | | Coverage | 100.0% (720/720) | | Median absolute hourly return | 0.28% | | 99th percentile of absolute hourly returns | 2.05% | | BTC beta | 1.42 | | Source / cutoff (UTC) | OKX · USDT / 21/10/2026, 04:38 | ## Claims and open questions - Anza said validators retired TowerBFT and activated Alpenglow at slot 459,653,000, cutting the time for a transaction to become irreversible from about 12.8 seconds to roughly 150 milliseconds, Decrypt reported. - Anza CEO Brennan Watt said the upgrade is "the largest, most ambitious blockchain upgrade since 'The Merge'" and was taken from white paper to mainnet in under 18 months, according to Decrypt. - Cointelegraph reported that Alpenglow, Solana's first major consensus upgrade, targets a 99% reduction in finality time. - Does the roughly 150-millisecond finality target hold consistently on mainnet under production load, and what mainnet data would Anza publish to confirm it? - How much cheaper are validator costs under Alpenglow's admission-ticket model compared with the previous vote fees, and will Anza or the Solana Foundation publish figures? ## Source evidence - [Solana’s Alpenglow, its biggest network overhaul since 2020, goes live Wednesday]() — CoinDesk; published 21/10/2026, 04:35; received 21/10/2026, 04:38 (UTC). - [Solana’s Alpenglow launches on mainnet, targets 99% faster finality]() — Cointelegraph; published 21/10/2026, 13:57; received 21/10/2026, 14:02 (UTC). - [Solana Alpenglow Goes Live in 'Most Ambitious' Upgrade Since Ethereum's Merge]() — Decrypt; published 21/10/2026, 14:24; received 21/10/2026, 14:27 (UTC). ## Recent SOL events and market reactions - [Why did SOL move -1.59% in 5 minutes? Evidence check: Solana falls as most tracked coins move lower · 2026-10-20]() — Received 20/10/2026, 15:14 (UTC) · Cause unresolved · Market watch · 5m -0.16% / 1h +0.64% / 24h +2.63% - [Solana study models geo-aware leader schedule proposal SIMD-0675]() — Published 14/10/2026, 15:05 (UTC) · Official source (1 publisher) · General news · 1h -0.32% - [SkyAI sells entire Solana treasury and launches $201 million buyback]() — Published 19/10/2026, 21:04 (UTC) · Multiple publishers (2 publishers) · General news · 1h -0.32% - [Full coin archive]() ## Research for this archive - [Altcoin beta to Bitcoin: BTC, ETH, SOL and DOGE hourly returns]() - [Perpetual funding rates and annualized yield: a 2025 comparison]() - [Crypto listing and delisting effects: an OKX price study]() - [Do token unlocks lower prices? SUI, SOL and high FDV claims]() [Methods and limitations]() Publisher count is not independent evidence count. Price changes cannot verify news or prove causation.