Idle stablecoins are cash under a mattress
Most people who hold USDC treat it like digital cash — a stable place to park value between spending, sending, or converting. That's a fair use of a stablecoin. But cash sitting in a wallet, digital or physical, does exactly one thing: it stays the same size. It doesn't grow, it doesn't shrink, and unlike cash in a mattress it doesn't even give you the peace of mind of being physically in your hand.
Meanwhile, there's an entire layer of established lending markets — the same ones banks and trading desks use — where those same dollars could be earning something instead of sitting still. The gap for most people isn't a lack of yield opportunities. It's that accessing them has historically meant learning a separate app, bridging funds to another chain, or trusting an unfamiliar protocol with money you can't afford to lose track of.
FAX closes that gap without asking you to leave the wallet you already use for everyday spending and sending.
How it works on FAX
Earning yield on FAX lives in the Grow tab, and it's built to be as plain as moving money between two balances:
- Open Grow > Yield. FAX shows you the current rate for each available vault before you deposit anything — no surprises after the fact.
- Deposit. You choose how much USDC (or, where available, EURC) to put to work. That amount moves out of your available balance and into the lending market.
- It earns. Your deposit is now lent out inside an established, audited DeFi lending protocol — specifically Aave or Morpho, depending on the vault. Rates float with market conditions, the same way any lending market's rate moves with supply and demand.
- Withdraw whenever. There's no lockup period. Your undeployed USDC earns a competitive APY automatically, and you can pull funds back to your spendable balance any time you want.
Nothing about the deposit or withdrawal requires you to understand Aave's or Morpho's interfaces, hold a separate gas token, or manually approve smart contracts one by one. FAX handles the mechanics; you see a balance that's earning and a button to withdraw it.
Why two providers
FAX connects to these lending markets through two integration partners: Pods Finance and vaults.fyi.
Pods Finance is the core of the feature. It covers a curated set of USDC vaults on Base and Polygon, built on top of Aave and a handful of Morpho vaults. Rather than exposing every vault in Pods' catalog, FAX hand-picks and vets which ones actually get offered in the app — the goal is coverage you can trust, not the largest possible list.
vaults.fyi extends that coverage to assets Pods doesn't support yet, starting with EURC — the euro-backed stablecoin — on Base. This is additive: it doesn't replace anything Pods already offers, it just means FAX users holding EURC get the same kind of access that USDC holders already have.
The result is more coverage across more assets, without FAX giving up its own vetting. Every vault offered through either provider, whichever one is powering it, has been reviewed and whitelisted by FAX before it shows up in your Grow tab.
Is this safe?
It's worth being direct about what this is and isn't.
The architecture is non-custodial. When you deposit, your funds move directly from your own wallet into the lending protocol's smart contract — Aave's or Morpho's, depending on the vault. FAX itself never takes custody of the funds along the way. That's a meaningful difference from handing money to a company that then decides what to do with it.
Your undeployed USDC earns a competitive APY automatically. No lockups. Withdraw any time.
Because the deposit path is non-custodial and direct to the protocol, you're never waiting on FAX, or anyone else, to release your funds. If you want your money back, you withdraw it.
That said, this is DeFi lending, not a bank savings account. It is not FDIC insured. Aave and Morpho are established, widely used, audited protocols — not experimental or unvetted contracts — but audited smart contracts still carry smart contract risk, the same way any software can. And the yield you earn is a floating market rate, not a fixed or guaranteed number: it moves with supply and demand in the underlying lending market, the same way any lending rate does.
What FAX controls is which vaults you're offered in the first place. Hand-picking and vetting each one before it's whitelisted is how FAX narrows the field down from "everything these protocols support" to a shorter list built around established, audited markets — but that vetting reduces risk, it doesn't eliminate it.
Put your idle USDC to work
Open FAX, head to Grow > Yield, and see the current rate before you deposit.