Solid Partners with Byzantine to Bring Insured Euro Yield
Three weeks ago we gave European cardholders zero fees on euro spending and said euro yield was next. It is live today, in partnership with Byzantine. Deposit EURC into Savings and your euros earn, in euros, the same way your dollars do in soUSD. Spend them by card with no FX fee, or keep them earning and spend on credit against them.
What’s new today
- A euro vault in Savings. Deposit EURC, receive soEURC, and your balance grows in euros.
- Up to 6% APY depending on market conditions, variable, with no USD/EUR exposure.
- Powered by Byzantine’s insured Byz Prime EUR vault, covered against technical risks.
- Yield Boost applies to soEURC: +2% for Prime, +3% for Ultra on top of the vault rate, paid in FUSE.
- Spend your euros by card with no FX fee, or turn on Credit mode and spend against your soEURC while it keeps earning.
- EURC deposits on Base are free.
Where the yield comes from
Your EURC goes into Byz Prime EUR, Byzantine’s audited, non-custodial vault on Ethereum mainnet. Returns come from interest paid by borrowers on lending markets such as Morpho and Aave, with the euro-dollar exposure hedged, so what you earn stays in euros.
Solid uses the insured version of the vault, which carries third-party cover against defined technical risks under Byzantine’s policy. You deposit on Base and Solid routes to mainnet for you, with no Ethereum gas. Your funds stay in your own wallet and can be verified onchain at any time.
Our partner: Byzantine
Byzantine is a Paris-based infrastructure provider that lets fintechs, wallets and neobanks add euro and dollar yield to their own apps. Returns come from borrower interest on digital credit markets, with strategies curated by a regulated Digital Asset Service Provider, and the same infrastructure is used by companies managing their treasury on Byzantine.
We connect directly to Byzantine’s vaults, so the app, the deposit flow and the withdrawal flow stay Solid’s while the yield engine is theirs. It is the first product we ship together, and it took weeks rather than months because the infrastructure was already there. Byzantine’s side of the story is in their announcement.
Yield Boost on your euros
Prime and Ultra now get their boost on soEURC too: +2% on the first $10K saved across all vaults for Prime, +3% on the first $25K for Ultra. It accrues daily, is claimed from the banner at the top of the vault, and is paid in FUSE by Solid on top of the vault rate.
Earn and spend in one currency
Pay euro purchases 1:1 from your EURC balance with no FX fee, or keep your euros earning as soEURC, switch your card to Credit mode, and spend against them. No FX fee either way, and in Credit mode your savings keep earning while you spend.
How to get started
- Open Savings and select the Euro vault.
- Deposit EURC on the Base network. The deposit is free.
- Your balance starts earning right away. Prime and Ultra see the Yield Boost banner at the top of the vault.
- To spend, set your main currency to Euro in Manage card, then pay from your balance or turn on Credit mode.
Who can use it
Solid cardholders whose card is issued in: the EU and EEA, the United Kingdom, Switzerland and the other Wirex countries.
Good to know
- Is the rate fixed? No. It moves with borrowing demand and the live rate is shown in the vault.
- What does “insured” mean? The vault carries cover against technical risks under Byzantine’s policy. It does not cover market losses, it is not a guarantee of returns, and your capital is at risk.
- Can I withdraw any time? Yes, back to your EURC balance from the app.
- Can I fund it from my bank? Not yet. For now the euro vault is funded with EURC on Base.
Euro Yield is available to Solid cardholders whose card is issued by Wirex. Deposits are held as EURC in your own non-custodial wallet and routed to the Byz Prime EUR insured vault operated by Byzantine Finance. The APY is variable, not guaranteed, and net of Solid’s fee on yield. The insurance covers technical risks only, as defined in Byzantine’s policy, not market losses, and is not a guarantee of capital or returns. Yield Boost is a Solid rewards programme for Prime and Ultra members, paid in FUSE, subject to the rules on the Rewards page. Credit mode is subject to its own terms shown in the app. Nothing here is investment or tax advice. Solid is a non-custodial platform and you control your keys and your funds.