Ostium
Ostium is an Arbitrum-based perpetuals venue offering leveraged exposure to 75 pairs across stocks, ETFs, commodities, indices, forex and crypto, settled in USDC against a liquidity vault and hedged off-chain with institutional partners.
Cost: One-time opening fee of 1-6 bps depending on asset class (crypto 6 bps, stocks/ETFs 3 bps), no closing fee, plus a $0.10 oracle fee per price request and a variable rollover fee. A $1,000 buy-and-sell costs about $0.60 in Ostium fees.
Sign-up perk: 2% boost to the referee's trading points at the referrer's Tier 1, up to 12% at Tier 5. No trading-fee discount is documented.
Checked 2026-10-16 · sources below- Round trip fee
- 0.06% buy + sell, platform fee
- $1,000 buy + sell
- $0.60 before network + pool fees
- US availability
- Not available UK: unverified · EU: unverified
- Custody
- non-custodial
- KYC
- none
- Platforms
- web
- Launched
- —
Users paid Ostium about $165K in fees in the 30 days to 2026-10-17 (DefiLlama) — a rough measure of how much it is actually used.
Best for: Traders who want onchain leveraged exposure to stocks, forex, commodities and indices from a self-custodied wallet, outside the US.
Ostium fees
| Fee | Type | Rate | Applies to | Note |
|---|---|---|---|---|
| Opening fee: crypto | protocol | 0.06% | open | 6 bps on all 9 crypto pairs (live fee table, 2026-10-16). Charged once on entry; closing fee is 0 bps. |
| Opening fee: stocks | protocol | 0.03% | open | 3 bps on all 43 stock pairs. |
| Opening fee: ETFs | protocol | 0.03% | open | 3 bps on all 8 ETF pairs. |
| Opening fee: indices | protocol | 0.01% | open | 1 bp (US500, US100, US30) to 3 bps (GER40, UK100, HK50, JP225). |
| Opening fee: forex | protocol | 0.02% | open | 2 bps on majors (EUR/USD, GBP/USD, USD/JPY etc.); 5 bps on USD/KRW and USD/MXN. |
| Opening fee: commodities | protocol | 0.02% | open | 2 bps gold; 3 bps silver, WTI, Brent, copper; 5 bps platinum and palladium. |
| Oracle fee | other | $0.10 | Buy and sell | Per price request (market open, limit placement, cancel, partial close, collateral removal). Refunded on a successful full close. Capped at 10 USDC per transaction. |
| Rollover fee | other | — | Buy and sell | Continuous, two-sided carry cost derived from SOFR (stocks/ETFs/indices) or futures term structure/funding (commodities, forex, crypto) plus a 1-2% annualized premium. One side can collect. |
| Early-close fee | other | — | close | Profitable positions closed within 15 seconds pay 40 bps decaying linearly to 0, capped at realized profit. |
Perps: taker 0.06%, maker 0.06% — Crypto pairs: 6 bps opening fee for both market and limit orders, 0 bps closing. Other asset classes 1-5 bps. Docs prose states a 3-10 bps range; per-pair values above come from the docs' live fee table.
Platform fees only. On-chain network/priority fees, pool (LP) fees and price impact are extra and vary by trade.
Is Ostium legit?
Docs say collateral sits in segregated smart contracts. Users connect a Web3 wallet or log in by email, which creates a Privy-managed smart account on Arbitrum that Ostium says does not access user keys.
Backers: General Catalyst and Jump Crypto (co-led $20M Series A); plus a separate $4M strategic round from Coinbase Ventures, Wintermute, GSR, SIG and others ($20,000,000), 2025-12; General Catalyst, LocalGlobe (co-leads), 2023-10.
Incidents on record
- 2026-07-15: Oracle infrastructure exploit drains OLP vault. An attacker used compromised off-chain price infrastructure to submit fraudulent BTC-USD price reports, draining 23.75M USDC from the OLP liquidity vault. Ostium said it found no evidence of a smart-contract or multisig compromise and that trader collateral was unaffected. Trading resumed 2026-07-23; an LP recovery plan was still pending as of 2026-07-30 reporting. Source
Where Ostium is available
| Region | Status |
|---|---|
| United States | Not available |
| United Kingdom | Unverified |
| European Union | Unverified |
Terms of Use list the United States and comprehensively sanctioned territories (Iran, Syria, Cuba, North Korea, Crimea, Donetsk, Luhansk) as Restricted Jurisdictions and prohibit VPN circumvention. UK and EU are not named as restricted; sanctions clauses reference UK/EU lists. (source)
We report what the venue's own terms say. Don't use a VPN to get around restrictions; venues can freeze accounts that do.
Pros and cons
Pros
- Covers 75 pairs across stocks, ETFs, commodities, indices, forex and crypto, which most crypto perp venues do not list.
- Fee is charged once on opening with 0 bps on close; major index pairs cost 1 bp and forex majors 2 bps.
- Collateral is held in segregated smart contracts, and email login creates a self-managed smart account.
- Rollover is two-sided, so one side of a pair can collect carry instead of paying it.
Cons
- A July 2026 oracle exploit drained 23.75M USDC from the OLP vault and paused trading for about a week.
- US persons are barred by the Terms of Use.
- A $0.10 oracle fee applies to most actions and is not refunded on partial closes, cancels or failed opens.
- Referral rewards are points boosts, not documented fee discounts.
Features
perpsstock perpsforex perpscommodity perpsindex perpslimit ordersstop-loss/take-profitemail login1-click tradingliquidity vaultAPI/SDKbuilder codes
Alternatives to Ostium
Lighter
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Paradex
Non-US traders who place orders manually through a web UI and want zero-fee perps plus options from one margin account.
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Aster
Non-US, non-UK traders who want zero maker fees on order-book perps, very high leverage modes, or privacy-shielded orders.
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Pacifica
Solana perp traders who want a published volume ladder, 50x leverage on majors and exposure to RWA and pre-IPO markets, and who are outside the United States.
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Where Ostium ranks
- #6 in Best on-chain platforms for stock perpsof 6
Ostium FAQ
Is Ostium legit?
Ostium is an Arbitrum perpetuals protocol backed by a $20M Series A co-led by General Catalyst and Jump Crypto. On 2026-07-15 an off-chain oracle compromise drained 23.75M USDC from its liquidity vault; Ostium says trader collateral was unaffected, and trading resumed on 2026-07-23.
What are Ostium's trading fees?
Ostium charges a one-time opening fee and no closing fee. Per the docs' live fee table, crypto pairs cost 6 bps, stocks and ETFs 3 bps, forex majors 2 bps and US index pairs 1 bp. A $0.10 oracle fee and a variable rollover fee also apply.
Can US users trade on Ostium?
No. Ostium's Terms of Use name the United States as a Restricted Jurisdiction alongside comprehensively sanctioned regions, and they prohibit using a VPN to get around the restriction.
Does Ostium have funding rates?
No zero-sum funding rate is used. Ostium charges a rollover fee derived from real-world carry costs such as SOFR or futures term structure, plus a 1-2% annualized premium. Depending on the curve, one side of a pair can collect rollover.
Sources
Last checked . Fees and terms change often; the venue's own page wins if it disagrees with ours.
- Ostium Docs: Fees (live opening-fee table) — checked 2026-10-16
- Ostium Docs: Welcome to Ostium — checked 2026-10-16
- Ostium Docs: Connect Your Account — checked 2026-10-16
- Ostium Terms of Use (last updated 2025-09-25) — checked 2026-10-16
- Ostium Docs (deprecated): Referrals — checked 2026-10-16
- The Block: Ostium blames off-chain breach for $24 million exploit — checked 2026-10-16
- The Block: Ostium pauses trading after apparent $18 million vault exploit — checked 2026-10-16
- Fundz: Ostium Series A — checked 2026-10-16
- CB Insights: Ostium financials — checked 2026-10-16
- The Block - Ostium $24M funding (2025-12-03) — checked 2026-10-16