Arbitrum One vs Nova: Which One Should You Actually Use

Two chains, one team, different goals

Arbitrum is not one chain. It is two: Arbitrum One and Arbitrum Nova. Both are built by Offchain Labs, both settle to Ethereum, and both use the same Nitro stack. But they make different trade-offs between cost, speed, and security — and those trade-offs matter for which one you should use.

Arbitrum One is the original rollup. It posts all transaction data to Ethereum as blobs (since EIP-4844) or calldata (before that). Every transaction is fully verified by Ethereum's consensus. It is the most secure Arbitrum chain and holds the vast majority of Arbitrum's total value locked — about $15-20 billion in 2026.

Arbitrum Nova is an AnyTrust chain. Instead of posting all transaction data to Ethereum, it posts a data availability certificate signed by a committee of nodes. If even one committee member is honest, the data is available. This makes Nova much cheaper — roughly 5-10x cheaper than One for data-heavy transactions — but introduces a committee trust assumption that One does not have.

If you are new to Arbitrum generally, the Arbitrum gas fee guide covers the fee mechanics on One. This article focuses on the One vs Nova decision.

The security model difference

Arbitrum One's security is identical to every other optimistic rollup: all transaction data is posted to Ethereum, anyone can verify the state transition, and fraud proofs protect against invalid batches. The only trust assumption is that at least one honest watcher monitors the chain and submits fraud proofs when needed. This is the same model as Base and Optimism.

Arbitrum Nova replaces the full data availability with a committee-based model:

A committee of nodes (initially 6 members, expanding over time) holds the full transaction data off-chain.
Instead of posting all data to Ethereum, Nova posts a certificate signed by at least 2/3 of the committee, attesting that the data is available.
If the committee refuses to provide the data, the chain falls back to posting full data to Ethereum — a safety mechanism called the "data availability fallback."
The trust assumption: at least one committee member is honest and will provide the data if challenged. If all committee members collude to withhold data, the fallback activates, but there is a brief window where the chain could be disrupted.

In practice, the committee members are reputable entities — exchanges, infrastructure providers, staking services — with strong incentives to behave honestly. The risk of collusion is low. But it is not zero, and it is a different trust model from One's full Ethereum data availability.

The actual fee difference

Nova is cheaper because it avoids the L1 data fee for most transactions. The L1 data fee is the dominant cost component on Arbitrum One — typically 70-90% of the total transaction cost. By certifying data availability instead of posting full data, Nova reduces this component to near zero.

Transaction type	Arbitrum One	Arbitrum Nova	Nova savings
Simple ETH send	$0.001-0.003	$0.0002-0.001	~50-70%
ERC-20 transfer	$0.002-0.005	$0.0005-0.002	~60-75%
NFT mint	$0.05-0.20	$0.01-0.05	~70-80%
Contract deployment	$0.50-2.00	$0.10-0.50	~75-80%
Game transaction (data-heavy)	$0.10-0.50	$0.02-0.10	~80-85%

The savings are most dramatic for data-heavy transactions — NFT mints, game actions, large contract deployments. For simple transfers, the difference is pennies either way. The full Arbitrum fee breakdown is in the Arbitrum gas guide.

Who Nova is actually for

Nova is designed for high-volume, low-value transactions where cost matters more than maximum security. The main use cases in 2026:

Gaming. Blockchain games generate thousands of small transactions per player per session. Paying $0.10 per action on Arbitrum One makes many game economies unviable. On Nova, the same action costs $0.02 — enough of a difference to make free-to-play models work.
Social apps. Onchain social platforms (Farcaster-like apps on Nova) generate frequent, low-value interactions — likes, follows, posts. Nova's cost makes these interactions economically feasible at scale.
NFT minting and trading. High-volume NFT collections that want to minimize mint costs for users. A $0.05 mint on Nova versus $0.20 on One is the difference between a free mint that breaks even and one that loses money on gas.
High-frequency trading bots. Bots that execute hundreds of transactions per hour need the lowest possible per-transaction cost. Nova's sub-cent fees make high-frequency strategies viable that would be unprofitable on One.

What Nova is not for: storing large amounts of capital, executing high-value DeFi transactions, or holding long-term positions. For those use cases, the additional trust assumption of the AnyTrust committee is not worth the gas savings. The L2 security risks guide covers why different trust models matter for different amounts.

The ecosystem gap: why most users ignore Nova

Despite being cheaper, Nova has a fraction of One's usage. The reason is ecosystem maturity. Arbitrum One launched in 2021 and has had years to accumulate DeFi protocols, NFT marketplaces, and developer tools. Nova launched in 2022 and has focused on gaming and social apps — verticals that have smaller user bases than DeFi.

In 2026, the DeFi ecosystem on Nova is minimal compared to One. There is no native Aave, no native Uniswap, no native GMX. The major DeFi protocols are all on One. If you want to do yield farming, lending, or derivatives trading, One is the only practical choice. Nova's strength is in gaming (Treasure ecosystem, several live games) and social (a few experimental apps), not in financial infrastructure.

This creates a self-reinforcing cycle: DeFi users go to One because the apps are there, which attracts more DeFi developers to One, which makes One even more dominant. Nova's lower fees are not enough to overcome the network effects of One's app ecosystem for most users.

How to move between One and Nova

Moving assets between Arbitrum One and Arbitrum Nova is straightforward. The official Arbitrum bridge (bridge.arbitrum.io) supports both chains. Select One as the source and Nova as the destination, enter the amount, and confirm. The transfer is an L2-to-L2 bridge within the Arbitrum ecosystem, so it is fast (under 10 minutes) and cheap (about $0.01-0.05 in gas).

Not all tokens are supported on both chains. ETH and major stablecoins (USDC, USDT) bridge easily. Smaller tokens and NFTs may not have a Nova equivalent — check the bridge UI before attempting a transfer. If a token is not supported, you need to swap it to ETH or a major stablecoin on One first, then bridge.

For bridging from other chains to Arbitrum generally — Ethereum mainnet, Base, Optimism — the Arbitrum bridging guide has the full breakdown.

Which one should you use

Use Arbitrum One for:

DeFi (lending, DEX swaps, derivatives, yield farming)
Holding significant capital ($1,000+)
Transactions where security is more important than saving a few cents
Interacting with major protocols (Aave, Uniswap, GMX, Camelot)

Use Arbitrum Nova for:

Gaming (Treasure ecosystem, onchain games)
High-frequency, low-value transactions
NFT minting for high-volume collections
Social apps and experimental onchain interactions
Situations where cost is the primary constraint

For most users, the answer is One. Nova is a specialized tool for specific use cases, not a general-purpose replacement. The gas savings are real but only matter at scale — if you are doing 10 transactions a month, the difference between One and Nova is under a dollar. If you are running a game with 10,000 daily active users, the difference is thousands of dollars per day.

The broader context: Arbitrum One is one of the cheapest major L2s already, and the cheapest L2 ranking shows it consistently in the top tier. Nova is cheaper still, but the ecosystem gap means most users never need it. Start with One. Switch to Nova only if you find yourself doing transaction types where the cost difference is meaningful.