The short answerAcross inverts the bridge model: a relayer pays you immediately on the destination chain and is reimbursed later from a shared pool, so the party taking cross-chain risk is the one being paid for it. Security rests on UMA's optimistic oracle with an economic dispute window rather than a bridge committee.
Best forFast, cheap EVM transfers with relayer-borne risk
Trust assumptionsweight 30%
8.5avg 7.2
Exploit historyweight 25%
9.5avg 8.8
Settlement speedweight 15%
9.5avg 8.3
Chain coverageweight 15%
8.0avg 8.1
Costweight 15%
9.0avg 8.2
this service category average across 15Score = Σ mark × weight. Recommendable to most readers, with stated caveats. Methodology.
| Criterion | Mark | What we found | Source | Checked |
|---|
| Trust assumptions | 8.5 | not sourced yet | not sourced yet | — |
| Exploit history | 9.5 | not sourced yet | not sourced yet | — |
| Settlement speed | 9.5 | not sourced yet | not sourced yet | — |
| Chain coverage | 8.0 | not sourced yet | not sourced yet | — |
| Cost | 9.0 | not sourced yet | not sourced yet | — |
What we liked, and what fell short
Liked- Transfers typically settle in seconds
- Relayers, not users, carry the cross-chain settlement risk
- No custom validator set — disputes resolve through UMA's optimistic oracle
Fell short- Depends on UMA's dispute mechanism functioning correctly
- EVM chains only
Why the marks landed where they did
Most bridges make the user wait while a validator set confirms a transfer. Across makes a professional relayer front the money instantly and take the waiting risk themselves, in exchange for a fee. For the user the transfer settles in seconds; for the relayer it is a financing business.
How settlement actually works
Relayers fill user requests on the destination chain from their own inventory. Periodically they submit a bundle claiming reimbursement from the shared liquidity pool. That claim is subject to UMA's optimistic oracle: it is assumed valid unless disputed within a challenge window, with economic penalties for false claims and false disputes. There is no custom validator set holding your funds.
Why this is a better risk profile
The user is never exposed to a locked collateral pool being drained mid-transfer, because the funds arrive before settlement occurs. The residual risks are the correctness of the optimistic oracle's dispute mechanism and the solvency of the shared pool, both of which are bounded and inspectable.
Costs and coverage
Fees typically run 0.05% to 0.2% depending on route and size, which is competitive, plus gas. Coverage is EVM chains — Ethereum, its major L2s and several sidechains — with no support for Solana or non-EVM ecosystems.
Who should use it
Anyone moving assets between EVM chains, particularly between L2s where speed matters. It is one of the two or three bridges we would use without hesitation.
FAQ
Why is Across so fast?+
A relayer pays you from their own inventory on the destination chain immediately, then claims reimbursement afterwards. You are not waiting for cross-chain settlement.
Who takes the risk in an Across transfer?+
The relayer, who fronts the funds and is reimbursed later subject to an optimistic oracle challenge window. The user's funds are not held in a vulnerable pool.
What does Across cost?+
Typically 0.05% to 0.2% depending on route and size, plus gas — competitive with any bridge.
Which chains does Across support?+
EVM chains including Ethereum and its major layer-2s. It does not support Solana or other non-EVM ecosystems.
