# OpenSea Moves NFT Trading to Seaport to Cut Costs and Add Flexibility

> On June 14, 2022, OpenSea began running its NFT marketplace on Seaport, an open-source trading protocol it had unveiled a month earlier. The switch cut typical gas costs, removed a one-time setup fee for new users and made offers on whole collections possible, at a time when NFT trading was cooling and rivals were competing on fees.

Source: https://cryptomorrow.com/2022/06/14/opensea-moves-nft-trading-to-seaport-to-cut-costs-and-add-flexibility/
Last checked: 2026-11-06

[OpenSea](https://opensea.io) began migrating its NFT marketplace to the [Seaport protocol](https://github.com/ProjectOpenSea/seaport) on June 14, 2022, replacing the older Wyvern-based contracts it had used since its early days. In a [launch post](https://opensea.io/blog/articles/launching-seaport-saving-the-community-millions-in-fees), the company pitched the change to collectors in practical terms: lower transaction costs, no setup fee for new users and new ways to make offers.

*Historical news event: 2022-06-14. Retrospective report prepared November 2026.*

Seaport itself wasn't new that day. OpenSea had [introduced the protocol](https://opensea.io/blog/articles/introducing-seaport-protocol) on May 20, 2022. June 14 was when the biggest NFT marketplace actually started routing its trades through it, which is a separate and arguably more important milestone.

## A marketplace protocol, not another NFT collection

Most NFT marketplaces at the time handled a simple trade: one person supplies an NFT and the other pays with a token. Seaport uses a more general model. A seller makes an "offer" of any mix of ETH, ERC-20 tokens and NFTs, and sets out the "consideration", the items they want back and who should receive them. Buyers can fill one listing or match several at once, which cuts out redundant transfers, the most expensive part of a trade.

The design also supports offers based on criteria instead of a specific token, so a buyer can bid on anything in a collection or anything with a certain trait. Prices can rise or fall over time for auctions, and orders can be partly filled.

OpenSea stressed that the protocol wasn't only for its own use. "OpenSea does not control or operate the Seaport protocol," the protocol's lead developer, known as 0age, wrote in the May 20 announcement, describing the company as one of many builders on a shared standard. The core contract had no owner and couldn't be upgraded.

Before launch, Seaport was reviewed by OpenZeppelin and audited by Trail of Bits, and OpenSea ran a two-week public audit contest with Code4rena with a $1 million prize pool, which it called the largest in that platform's history.

## What changed for buyers and sellers

The June 14 post listed four changes users would notice right away:

- Lower gas fees on most transactions.
- Offers on entire collections, and "attribute offers" on items with specific traits, starting with the top 100 collections by 30-day volume.
- No account initialisation fee for new users. Under the old system, first-time sellers paid to deploy a "proxy" contract.
- Wallet signature requests that were easier to read.

"You'll save an estimated 35% in gas fees for transactions using Seaport," Aadil Mamujee wrote in OpenSea's June 14 announcement. The company estimated that, based on the previous year's activity, the savings would have totalled more than $460 million, and that dropping the setup fee alone could save users almost $120 million a year. Those were company estimates based on past data, not audited figures.

![Seaport logo beside text reading 'On average Seaport is 34.8% more cost effective than Wyvern Protocol'](/static/up/2022/06/cm-017-seaport-average-gas-savings-chart.webp)

*Image: [OpenSea](https://opensea.io)*

There was a catch. To get lower fees when selling or transferring, users had to approve each collection for the new contracts, a one-time cost per collection. OpenSea said existing listings wouldn't be affected by the migration.

The company also said Seaport would let it ship features faster, naming bulk purchases in a single transaction and onchain creator fees split between several recipients as next steps.

## Why plumbing matters in Web3

NFT stories usually focus on artwork and headline sales. Behind every trade is a set of smart contracts that handle approvals, transfers, payments and marketplace rules. A protocol change like this one altered the cost and options for trading across thousands of collections without touching a single image.

The timing mattered too. By June 2022 the NFT market was cooling sharply after its 2021 peak, and OpenSea faced rivals competing on price. LooksRare had launched earlier that year [with token rewards aimed squarely at OpenSea's traders](/2022/01/10/looksrare-challenges-opensea-with-a-token-reward-model-for-nft-traders/). A marketplace couldn't control demand, but it could make each trade cheaper. Later in 2022, Blur arrived with zero-fee trading, and its founder went on to launch [the Blast layer 2](/2023/11/20/blur-founder-introduces-blast-an-ethereum-layer-2-with-native-yield/).

Opening the protocol was also a strategic bet. Other marketplaces and tools could build on the same order format, so listings could, in principle, be shared across platforms. Openness didn't remove smart-contract risk, but it meant the code could be examined by anyone, and OpenSea invited developers to review it.

## How Seaport held up

Seaport became OpenSea's core trading layer and was adopted by other marketplaces and aggregators over the following years. OpenSea itself kept evolving on top of it, and in 2025 rebuilt its platform as [OS2, adding token trading across many chains](/2025/02/13/opensea-unveils-os2-beta-combining-nfts-and-tokens-across-chains/).

Looking back, the June 2022 migration is a reminder that some of the most useful changes in crypto look less like a token launch and more like removing a step, and a fee, from an everyday task.

## Frequently asked questions

### What is OpenSea Seaport?

Seaport is an open-source smart contract protocol for buying and selling NFTs on Ethereum and compatible chains. It lets traders swap any mix of ETH, tokens and NFTs in a single order.

### When did OpenSea switch to Seaport?

OpenSea introduced the Seaport protocol on May 20, 2022, and began migrating its marketplace to it on June 14, 2022.

### How much did Seaport reduce gas fees?

OpenSea estimated that users would save about 35% in gas fees on transactions using Seaport compared with its previous Wyvern-based system. New users also no longer paid a one-time account setup fee.

### What replaced Wyvern on OpenSea?

Seaport replaced the Wyvern protocol that OpenSea had used for its marketplace contracts before June 2022.

### Is Seaport only for OpenSea?

No. The core contract has no owner and is open source, so other marketplaces and developers can build on it. OpenSea said it is one of many builders using the protocol.

## Sources

- [OpenSea: Launching Seaport and saving the community millions in fees (June 14, 2022)](https://opensea.io/blog/articles/launching-seaport-saving-the-community-millions-in-fees)
- [OpenSea: Introducing Seaport protocol (May 20, 2022)](https://opensea.io/blog/articles/introducing-seaport-protocol)
- [Seaport source code on GitHub](https://github.com/ProjectOpenSea/seaport)
- [Code4rena: OpenSea Seaport audit contest report (2022)](https://code4rena.com/reports/2022-05-opensea-seaport)
- [OpenSea developer documentation: Seaport](https://docs.opensea.io/docs/seaport)

*Featured image: [OpenSea](https://opensea.io)*