Most blockchains the wallet touches use probabilistic finality. Bitcoin's "wait 6 confirmations" exists because the chain you see now might be reorganised by a longer chain that surfaces later. Ethereum has the same property — a 12-second slot can be re-org'd; the modern guidance is to wait for the finalized checkpoint, ~12 minutes later.
Cosmos is different. Tendermint (now CometBFT) gives deterministic, single-round finality in roughly 6 seconds. Once a block is committed, it is final. There are no reorgs. The wallet can show "confirmed" the instant the block lands.
Why this matters for you
If you send 100 ATOM to a friend, the moment the receipt comes back, the transfer is final. You don't need to wait for confirmations. The flash-success message in the UI is telling you the truth — there's no "but actually wait an hour" caveat.
This is also why Cosmos-based exchanges (Osmosis DEX, Kava money market) have such fast UIs. They aren't waiting on a probabilistic confirmation horizon.
The trade-off
Single-round finality requires a known validator set. Cosmos Hub has 180 active validators producing blocks. Each validator stakes ATOM; the stake is slashed if they sign two conflicting blocks (double-signing) or if they're offline for too long.
Compared to Bitcoin's open-membership PoW or Ethereum's open-membership PoS:
- Faster: 6-second finality vs 12 minutes (ETH) or 60 minutes (BTC for €1k+).
- Smaller validator set: 180 vs Ethereum's ~1 million validators. Higher concentration of trust.
- No reorgs: Once committed, immutable. Period.
The wallet treats this as a feature. A confirmed Cosmos tx is treated as final immediately; we don't wait for additional blocks.
Voting power and ⅔ supermajority
A block is committed when validators representing ≥ ⅔ of staked ATOM sign a "precommit" message for that block. If you control 1/3 of the stake, you can halt the chain (refuse to sign). If you control 2/3, you can produce blocks unilaterally. Outside those thresholds, the protocol is safe.
This is why the nakamoto coefficient (number of validators needed to halt the chain) matters. The Hub's current coefficient is around 7 — concerning, but in line with most BFT chains.
What can go wrong
Liveness halts. If ⅔ of stake goes offline (cloud outage, coordinated downtime), the chain stops producing blocks until enough validators come back. Cosmos has experienced several short halts. The wallet treats a stuck tip as "RPC degraded" and surfaces it in the network-health pill.
Slashing cascades. If a major validator double-signs and gets slashed, delegators (people who staked through them) also get slashed. The wallet doesn't expose staking in iter-G, but if you delegate ATOM elsewhere, pick your validator carefully.
Validator capture. A small enough set is plausibly captured by external pressure. Cosmos Hub mitigates this with the IBC ecosystem — the Hub is one chain among many, not a load-bearing monopoly.
The TL;DR
When you send ATOM or OSMO, the moment the wallet says "confirmed" the transfer is final. Tendermint gives you single-round Byzantine fault-tolerant finality in ~6 seconds. You can spend the funds immediately on the receiving side. This is unlike every other chain in the wallet, and it's the single biggest UX advantage Cosmos has over its peers.
Next lesson: how the same key gives you two addresses — one for the Hub, one for Osmosis.