The short version
The common ground
KAST and ether.fi Cash share more DNA than their marketing suggests. Both are Visa cards issued by Third National, a Rain group company, which means the regulated card infrastructure underneath is the same family. Both target crypto-native spenders, both run tiered membership programs, and both require identity verification. Where they split is philosophy: KAST sells status tiers and yield on idle dollars, while ether.fi sells DeFi-native spending power with your assets staying in your own vault.
Cashback and tiers compared
The tier structures could not be more different. KAST charges cash for its tiers. ether.fi charges nothing annually and unlocks tiers through ecosystem points instead.
| Tier | Cost | Headline cashback | Monthly cap |
|---|---|---|---|
| KAST Standard | Free | 1.5% | First $2,000/mo |
| KAST Premium | $1,000/year | 2% + 1% in points | Standard spend |
| KAST Private | $10,000/year | 3% + 2% in points | Standard spend |
| ether.fi Core | Free (no annual fee) | 3% | First $2,000/mo |
| ether.fi Luxe | Unlocks at 5,000 points | 3% | First $10,000/mo |
| ether.fi Pinnacle | Unlocks at 25,000 points | 3% | First $50,000/mo |
| ether.fi VIP | Top tier (no annual fee) | 4% | Headline rate |
The math favors ether.fi for most people. Its free Core tier pays 3% on the first $2,000 of monthly spend, double KAST Standard's 1.5%. KAST only catches up at Private, where 3% cashback plus 2% back in points roughly matches ether.fi VIP's 4%, but Private costs $10,000 a year while ether.fi VIP costs nothing annually. KAST's real edge is not the card cashback at all: it is the USD Reserve account paying 8% to 12% annualized on idle balances until mid-2027.
Custody: who holds your money
ether.fi Cash is the cleaner self-custody story. Your assets sit in your own Vault, the issuer has no custody or control over wallet contents, and you choose how to spend: Direct Pay mode spends your balance, while Borrow mode lets you borrow against your crypto from 1.43% interest so you never have to sell a position to buy lunch. KAST's Earn vaults are also self-custodial (funds sit in your own Privy wallet with onchain proof of reserves), but the day-to-day card spending balance works like a conventional account. If non-custodial architecture is your deciding factor, ether.fi wins.
Fees compared
| Fee | KAST | ether.fi Cash |
|---|---|---|
| Annual / membership fee | Free / $1,000 / $10,000 per year | $0 on all tiers |
| Virtual card | Free | $10 on Core/Luxe/Pinnacle, free on VIP |
| Physical card | $40 | $50 Core, $100 Luxe/Pinnacle, free VIP |
| FX markup | Check in-app terms | 0.5% Core, 0.25% Luxe, none on Pinnacle/VIP |
| ATM | Check in-app terms | $5,000 per transaction, 5 per rolling 24h, $25,000 daily |
| Borrowing | Not offered | Borrow mode from 1.43% |
ether.fi publishes far more of its fee schedule, which makes it easier to price honestly. KAST's headline costs are the membership fees themselves; the $10,000 Private tier only makes sense if the Reserve yield and points value clearly exceed it on your balances.
Funding and availability
KAST funds from stablecoins with strict deposit rules: USDT on Solana for the primary path, and wrong-network deposits can be permanently lost. It advertises availability in 190+ countries. ether.fi funds from a non-custodial Vault plus bank transfers in 162 countries (USD ACH, wire, EUR SEPA, GBP Faster Payments, and more), with the physical card shipping to 31 US states. KAST wins on headline country count; ether.fi wins on funding rail variety.
Beyond the card: what else each app does
KAST
- USD Reserve account paying 8% to 12% annualized until mid-2027 (then 4%), funded by KAST as a promotion
- Self-custodial Earn vaults: USDKY via the M0 protocol (backed by short-term US Treasury bills) and a Gauntlet-curated vault, no lock-ups
- Visa Infinite benefits on Premium and Private tiers, VIP concierge on Private
- Apple Pay and Google Pay support
ether.fi Cash
- Borrow mode from 1.43%: spend against crypto collateral without selling
- 5% cashback on ether.fi Travel bookings plus up to 65% off hotels and flights
- Airport lounge access, Visa concierge, global eSIM, purchase and price protection
- Balance protection up to $500K on VIP
The honest caveats
KAST's boosted Reserve rates are a KAST-funded promotion ending mid-2027, not a permanent yield. KAST is not a bank, and its Earn vaults carry DeFi smart-contract risk. ether.fi's Borrow mode accrues interest from 1.43%, and crypto collateral can lose value; the issuer explicitly has no custody or control over your wallet, which is a feature until something goes wrong and there is no one to call. Both cards require KYC, and both sets of terms can change.
The verdict
Choose KAST if you keep large USD balances idle and want them earning 8% to 12% until mid-2027, or if you spend enough to justify the Premium or Private tiers and value Visa Infinite status perks. The card is the accessory; the Reserve account is the product.
Choose ether.fi Cash if you want the best free-tier deal in this comparison (3% on the first $2,000 of monthly spend with no annual fee), if keeping custody of your assets matters to you, or if you want to spend against crypto without selling it. The Borrow mode is something KAST simply does not offer.
For most beginners, ether.fi Core is the easier yes: higher cashback than KAST Standard, no membership fee, and a genuinely non-custodial design. KAST makes sense once your balances are large enough that the Reserve yield dwarfs the membership cost.
Affiliate disclosure
Frequently asked questions
What do KAST and ether.fi Cash have in common?
More than you might expect. Both are Visa cards issued by Third National, a Rain group company, so the card plumbing underneath is the same family. Both target crypto-native users who want to spend stablecoins or crypto without a traditional bank account in the middle, and both use tiered membership programs to gate their best rewards. Both also require identity verification.
Which has better cashback, KAST or ether.fi?
It depends on what you pay for the tier. ether.fi gives 3% cashback on every tier including the entry-level Core, with monthly caps of $2,000 (Core), $10,000 (Luxe), and $50,000 (Pinnacle); VIP gets 4%. KAST's free Standard tier gives 1.5%, Premium ($1,000/year) gives 2% plus 1% back in points, and Private ($10,000/year) gives 3% plus 2% back in points. On the free or entry tiers, ether.fi's 3% beats KAST's 1.5%. On the top paid tiers, KAST Private matches ether.fi VIP at 3% to 4% headline, but costs $10,000 a year for the privilege.
Do KAST and ether.fi charge annual fees?
Differently. KAST's tiers are paid memberships: Standard is free, Premium costs $1,000 per year, and Private costs $10,000 per year. ether.fi Cash has no annual fee on any tier; instead, higher tiers unlock through points earned in the ecosystem (Luxe at 5,000 points, Pinnacle at 25,000 points). So ether.fi rewards activity while KAST charges cash for status.
Are both cards self-custodial?
Partially, and the details matter. ether.fi Cash is non-custodial by design: your assets sit in your own Vault and the issuer has no custody or control over wallet contents. You spend in Direct Pay mode or borrow against your assets in Borrow mode from 1.43%. KAST's Earn vaults are self-custodial (funds sit in your own Privy wallet with onchain proof of reserves), but the card spending account itself is a more conventional balance. If keeping custody of everything is your priority, ether.fi's model is cleaner.
Which card is better for travel?
ether.fi publishes a clear FX schedule: 0.5% markup on Core, 0.25% on Luxe, and zero on Pinnacle and VIP, plus 5% cashback on ether.fi Travel bookings with up to 65% off hotels and flights, airport lounge access, and Visa concierge. KAST leans on Visa Infinite benefits on its higher tiers but does not advertise the same travel-booking rewards stack. For frequent travelers, ether.fi's published perks are easier to value.
What is KAST's USD Reserve account?
A USD balance inside the KAST app that pays daily cash rewards: 8% annualized on Standard, 10% on Premium, and 12% on Private. These are boosted promotional rates funded by KAST that run until mid-2027, then drop to 4%. KAST is not a bank, so this is a promotional yield, not insured savings. It is the single biggest reason to pick KAST over ether.fi if you keep large idle USD balances.