How to Bridge from Polygon to Arbitrum (Cross-Chain Swap Guide)

Introduction – Why Bridge from Polygon to Arbitrum?

In today’s multi-chain DeFi landscape, liquidity, users and dApps are scattered across dozens of networks. A cross-chain bridge lets you move value between these otherwise siloed chains, unlocking true blockchain interoperability and ensuring you can chase opportunities wherever they appear. Bridges work by locking your tokens on the source chain and minting (or releasing) an equivalent amount on the destination chain, so you keep uninterrupted ownership while hopping networks. They have become essential plumbing for Web3, accounting for billions of dollars in weekly volume. Bridging assets, such as when you bridge MATIC (the full name of Polygon's native token), is a common use case for users seeking to move tokens between networks.

So why specifically move assets from Polygon to Arbitrum? While Polygon remains a popular side-chain for low-fee trading (average fees ≈ $0.015 per transaction), its key features include scalability, fast transactions, and low fees, making it attractive for DeFi users. Arbitrum has rapidly evolved into the largest Ethereum Layer-2 roll-up by usage.

As of June 2025 it sits in the global top-10 with ≈ $2.1 billion TVL and has processed over $100 billion in DEX volume this year alone. Its roll-up design delivers Ethereum-level security with fees that average about $0.02—a fraction of main-net costs and fast enough for complex DeFi strategies. Both Polygon and Arbitrum offer low transaction fees, which is a major benefit for users. Bridging, then, isn’t just about shaving cents off gas; it’s about tapping Arbitrum-native yield farms, perpetuals, and on-chain games that don’t exist (or are more expensive) on Polygon.

There’s a technical hurdle, though: Polygon (a PoS side-chain) and Arbitrum (an optimistic roll-up) are entirely separate Layer-2 environments that interact with the Ethereum main chain in different ways. Their consensus layers, sequencers and state roots don’t talk to each other, so a direct token transfer is impossible without an intermediary. That’s where a purpose-built bridge adds real bridging benefits—guaranteeing finality on Polygon, executing the hand-off, and releasing funds on Arbitrum with minimal user friction.

The functionality of Arbitrum's optimistic roll-up technology enables scalable and cost-effective execution of smart contracts and decentralized applications. Ongoing development by teams like Offchain Labs and Polygon continues to drive innovation and scalability across these platforms.

When bridging assets, users will be paying transaction fees in the native token (MATIC on Polygon, ETH on Arbitrum). The process often requires connecting wallets to the bridge to manage and authorize asset transfers. Additionally, an exchange or swapping mechanism is typically used to facilitate the movement of assets between networks.

Throughout this guide we’ll use Relay, a modern liquidity-network bridge, to perform a seamless cross-chain swap from Polygon to Arbitrum. Relay abstracts away contract calls and routing complexities, turning what once required multiple transactions and long wait times into a single, near-instant operation. By the end of the walkthrough you’ll see how Relay makes Layer-2 interoperability as easy as a normal wallet transfer—so you can focus on the strategy, not the plumbing.

Understanding Polygon and Arbitrum Networks

Polygon network ↔ sidechain scalability.
Polygon (formerly Matic) began life as a Proof-of-Stake sidechain that checkpoints to Ethereum. Because transactions settle on its own validator set before being batched to Ethereum, it offers lightning-fast throughput—up to 65 000 TPS in stress tests—while keeping the typical on-chain cost at roughly $0.015 per swap or NFT mint. These rock-bottom fees have made Polygon a favorite for retail-facing DeFi, gaming, and mass-mint NFT drops; brands from Nike to Reddit run on it precisely because users don’t blink at gas costs.

Arbitrum network ↔ Ethereum-secured roll-up.
Arbitrum takes a different path. It is an optimistic roll-up: transactions execute off-chain, but the roll-up periodically posts compressed data and fraud proofs to Ethereum, inheriting L1 security while slashing costs. The result is a network that clears ≈ $0.02 per transaction, secures more than $12 billion in TVL, and handles ~1.5 million daily transactions—today’s largest Layer-2 by both value and activity. For traders, that means deep liquidity on native dApps like perpetual DEXs and money markets that don’t exist (or are pricier) on Polygon.

Why move assets between them?
Even though both live in the Ethereum universe, Polygon and Arbitrum are separate Layer-2 environments. Their consensus layers and state roots never touch, so a token that lives on Polygon can’t magically appear on Arbitrum. A cross-chain bridge is the only way to hop the gap—locking funds on Polygon while releasing an equivalent amount on Arbitrum. Without bridges, blockchains remain “islands in an ocean,” unable to share value or data. Practically, bridging lets users:

• tap Arbitrum-only dApps (e.g., high-leverage perp platforms) while starting from Polygon;
• arbitrage or farm where yields are higher;
• keep fees low across the journey by avoiding Ethereum L1 entirely.

Because the networks are siloed by design, bridging tools like Relay become essential middleware—securing assets on the source chain, handling the cross-chain accounting, and delivering funds to the destination in one near-instant step.

Meet Relay – A Cross-Chain Bridge for Seamless Swaps

Relay is a cross-chain bridging and swap platform built to make moving value between blockchains feel as quick and inexpensive as a same-chain transfer. Technically, it’s a “cross-chain payments system” that abstracts away gas juggling and routing complexity so users can click once and land on the destination network with funds in hand.

How Relay achieves instant, low-fee transfers

Instead of waiting for multi-party consensus like message–passing bridges, Relay relies on a network of bonded relayers. A relayer front-runs your transfer with its own liquidity on the destination chain, then settles up behind the scenes—so the swap typically finalises in 1-10 seconds and costs only a fraction of traditional bridges. The production-grade “Reservoir Relayer” currently anchors the system, handling order validation, execution, and periodic re-balancing of its chain balances.

Built for today’s multi-chain reality

Relay already plugs into 80-plus blockchains, including both Polygon and Arbitrum, giving you a single dashboard for almost any route you need. Its interface auto-detects tokens, quotes the all-in cost up front, and lets beginners bridge with the same ease that power users script cross-chain execution via the API or SDK.

Security and trust assumptions

While work on a fully permissionless protocol is under way, the current model is protected by multiple layers: audited smart contracts, a public bug-bounty program, bonded relayers that forfeit stake if they mis-behave, and a comprehensive user-facing security guide. Together, these safeguards let newcomers bridge confidently while still enjoying near-instant settlement.

Benefits of Using Relay to Bridge Polygon → Arbitrum

1. Fast — near-instant bridging
Relay’s relayer model “front-runs” your transaction with its own liquidity on Arbitrum, so most swaps land in seconds, not hours—no long finality waits like message-passing bridges.

2. Low fees & up to 70 % cost savings
By off-loading expensive validation logic to cheaper settlement layers and skipping pool-based liquidity hops, Relay often cuts total bridge costs by as much as 70 % compared with other Polygon↔Arbitrum routes. Typical gas footprint is ~42 k vs. 250 k for the next-cheapest alternative—serious savings whether you’re moving $50 or $50k.

3. Broad cross-chain & token support
Relay already plugs into 80 + blockchains, so you can hop straight from Polygon to Arbitrum without routing through Ethereum mainnet. Popular tokens—ETH, USDC, USDT, MATIC and dozens more—bridge natively, keeping your portfolio flexible across ecosystems.

4. User-friendly interface & wallet integration
The web app auto-detects your wallet (MetaMask, WalletConnect, etc.), quotes all-in fees up front, and guides beginners with clear prompts—yet still exposes granular data advanced users expect. One click, one confirm, and you’re done.

5. Secure & reliable architecture
Relay is operated by the Reservoir team and protected by:

• Bonded relayers—each relayer escrows funds, so users can claim compensation if a relay fails to deliver.
• Audited smart contracts & public bug-bounty program, offering rewards up to $100 k for responsibly disclosed vulnerabilities.

Because you bridge straight from your own wallet, there’s no custodial risk or centralized deposit—just a quick, low-cost, and secure path from Polygon to Arbitrum.

Gas Fees and Bridging: What to Expect

When bridging tokens from the Polygon network to the Arbitrum network, understanding gas fees is crucial for a smooth and cost-effective experience. Gas fees represent the cost of processing transactions on blockchain networks, and they play a key role in ensuring secure transactions as your assets move between the two networks. Each network—Polygon and Arbitrum—has its own fee structure, which can directly affect the total cost of bridging tokens.

On Polygon, users typically pay gas fees in the native token, MATIC, while on Arbitrum, fees are paid in ETH. The amount you pay can fluctuate based on network congestion and the complexity of the transaction. When bridging tokens, you’ll need to cover gas fees on both the source and destination networks, as the process involves interacting with smart contracts on each chain to lock and release your assets securely.

To keep costs low, users can monitor current gas prices and choose to bridge during periods of lower network activity. Many bridging platforms, including Relay, are designed to optimize for the lowest cost by batching transactions and leveraging efficient routing, making the process more cost effective. Always check the estimated fees before confirming your transaction, and ensure you have enough of the native token in your wallet to pay for gas on both Polygon and Arbitrum. By staying informed and choosing the right time and platform, you can minimize fees and enjoy a seamless, secure bridging experience from Polygon to Arbitrum.

Finding the Cheapest Way to Bridge from Polygon to Arbitrum

If your goal is to bridge tokens from Polygon to Arbitrum at the lowest cost, it pays to compare your options. Transaction fees and gas fees can vary widely between cross chain bridging platforms, so it’s important to do your research before initiating a transfer. Platforms like Chainport.io and Relay are known for offering competitive transaction fees and fast processing, but always review the latest rates and user feedback to ensure you’re getting the best deal.

To find the cheapest way to bridge, start by connecting your wallet—such as MetaMask—to both the Polygon and Arbitrum networks. Use the platform’s interface to compare estimated fees, including both the platform’s service fee and the underlying gas fees required for the transaction. Some platforms provide a dropdown menu to select different tokens or routes, allowing you to optimize for the lowest cost and fastest speeds.

Remember, while minimizing fees is important, security should never be compromised. Always choose reputable platforms with a track record of secure cross chain transactions. By balancing cost, speed, and security, users can bridge tokens efficiently and confidently, taking full advantage of the benefits offered by both Polygon and Arbitrum networks.

Preparation – What You Need Before Bridging

Getting ready takes only a few minutes, but skipping any of the steps below can delay (or even break) your Polygon → Arbitrum bridge. Double-check each item before you press “Bridge Now.”

With wallet, gas, and networks sorted, you’re fully prepped. The actual bridge is now just five clicks away and should complete in under a minute.

Step-by-Step Guide — Bridging from Polygon to Arbitrum with Relay

Below is a concise, click-for-click walkthrough that shows you exactly how to bridge Polygon to Arbitrum using the Relay web app. Keep your wallet (MetaMask or WalletConnect) open and be sure you’re on the official site — https://relay.link.

Step 1 | Connect your wallet to Relay

1. Go to Relay’s homepage and hit “Connect Wallet.”
2. Choose MetaMask (or any WalletConnect option) and approve the connection prompt.
3. Make sure MetaMask is already set to the Polygon network; Relay will read your Polygon balance as the funding source.

Tip: Always glance at the browser URL and the certificate lock before clicking Approve.

Step 2 | Set Polygon → Arbitrum as your route

1. In the Relay dashboard, open the network selector.
2. Under “From,” pick Polygon; under “To,” pick Arbitrum One.
3. Double-check the destination isn’t Arbitrum Nova or a testnet unless that’s your intent.

Step 3 | Choose the token & amount

1. Click the token dropdown and select what you want to move (e.g., ETH, USDC, USDT, MATIC).
2. Enter the amount. Relay will show an estimated receive amount on Arbitrum and flag any minimum/maximum.
3. New to bridging? Start with a small test (e.g., $10) before sending large sums.

Step 4 | Review & confirm the bridge

1. Relay now displays a summary: source chain, destination chain, token, amount, bridging fee, and your Arbitrum address.
2. If it’s your first time moving that token, MetaMask will ask for a one-time “Approve”; then you’ll see the “Bridge Now” transaction.
3. Hit Confirm in MetaMask. Relay’s relayer network takes over and pushes the funds across chains.

Step 5 | Wait a few seconds & verify on Arbitrum

Most swaps settle in under a minute.

1. When Relay shows “Success,” switch MetaMask to Arbitrum One.
2. If the token isn’t visible, click “Import Tokens,” paste the Arbitrum token contract, and add it.
3. Optionally paste the transaction hash into Arbiscan to see on-chain confirmation. Once the transfer is marked “Success” on Arbiscan, you’re done.

DeFi Protocols and Bridging: Unlocking New Opportunities

Bridging tokens from Polygon to Arbitrum isn’t just about moving assets—it’s about unlocking a world of new opportunities in the DeFi space. Both the Polygon ecosystem and the Arbitrum ecosystem are home to a diverse range of DeFi protocols, from decentralized exchanges and lending platforms to innovative stablecoin issuers and yield farms. By bridging tokens, users gain access to these decentralized applications and can interact with services that may not be available on their original network.

Providing liquidity across networks allows users to participate in new markets, earn rewards, and benefit from the unique features of each platform. For example, you might bridge USDC or MATIC from Polygon to Arbitrum to take advantage of lower gas fees, deeper liquidity pools, or exclusive DeFi protocols native to the Arbitrum network. This cross-chain flexibility helps reduce fragmentation in the DeFi landscape, making it easier for users and developers to access digital assets and build more robust, interconnected platforms.

As DeFi continues to evolve, bridging will remain a key tool for users looking to maximize their returns and engage with the latest decentralized applications. By leveraging the strengths of both Polygon and Arbitrum, you can provide liquidity, interact with new protocols, and participate in the growing world of multi-chain DeFi—all with the efficiency and security that modern bridging solutions provide.

Troubleshooting Common Issues

Best Practices & Safety Tips

1. Use only official links – bookmark https://relay.link and avoid look-alike domains.
2. Keep your wallet secure – update MetaMask, never reveal seed phrases, and consider a hardware wallet for large transfers.
3. Double-check every detail – token, amount, destination network, and address before clicking Confirm. A 5-second review can save a big headache.
4. Have a little ETH on Arbitrum – you’ll need it for gas once the tokens arrive; bridging 0.003 ETH along with your main asset usually covers several transactions.
5. Watch the explorer – Relay links directly to Arbiscan so you can track progress in real time; don’t close the tab until you see a green “Success.”

Follow these steps and pointers, and you’ll complete a fast, low-fee, and secure cross-chain swap from Polygon to Arbitrum using Relay every time.

Conclusion – Access Arbitrum’s Ecosystem with Ease

Bridging from Polygon to Arbitrum no longer requires complicated, multi-step work-arounds or expensive detours through Ethereum mainnet. With Relay’s cross-chain swap, the entire journey is reduced to a handful of clicks—connect, select, confirm, and you’re done. Thanks to Relay’s relayer network, assets arrive on Arbitrum in seconds, fees stay razor-thin, and you keep full custody of your wallet the whole time.

By moving funds through this seamless cross-chain route, you unlock Arbitrum’s fast, low-cost DeFi protocols, thriving NFT markets, and high-throughput games without abandoning the liquidity and community you already enjoy on Polygon. Relay’s support for 80-plus blockchains means today’s Polygon → Arbitrum hop is just the beginning; tomorrow you can route value to any network that offers new opportunities— all from the same, intuitive dashboard.

Whether you’re a crypto beginner exploring your first Layer-2, a DeFi power user chasing yield, or a developer building truly multi-chain DeFi apps, Relay puts the power of cross-chain composability at your fingertips. Follow the steps in this guide once, and you’ll be able to repeat the Polygon to Arbitrum bridge whenever you spot an opportunity—quickly, affordably, and with confidence.

Cross-chain interoperability is the future of Web3. Tools like Relay ensure that future is already here, letting you explore, trade, and build across ecosystems without friction. So go ahead—execute your first Relay cross-chain swap and experience the best of both worlds in Ethereum’s Layer-2 universe.