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StoneCastle review

Updated September 28, 2026 · SumCue Editorial Team · Facts checked September 26, 2026

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Our verdict

StoneCastle suits savers who prioritise easy access and low account charges over certainty about the return. Its easy-access account offers a variable headline rate of 3.5%, charges a monthly fee of $0, and requires a minimum deposit of $0. The trade-off is that the rate can change.

Key facts

Best for
Easy-access saving with a low minimum deposit and no monthly fee.
Headline rate
3.5%↗
Rate type
Variable↗
Minimum deposit
$0↗
Access terms
On-demand access; next business day liquidity, 3:00 PM ET cut-off for same-day deposit credit and next-day liquidity withdrawals↗
Monthly fee
$0↗
Account kind
Easy access↗
Legal entity
StoneCastle Cash Management, LLC↗
Headquarters
United States↗
Founded
2009↗
Support channels
Email, Phone↗
Pricing model
No monthly fee
Official website
stonecastle.com

Facts checked September 26, 2026, 5 sources

Apps and profiles

Elsewhere
LinkedIn

Pros and cons

Pros

  • The easy-access account has a headline rate of 3.5%.
  • The easy-access account requires a minimum deposit of $0.
  • The easy-access account has a monthly fee of $0.
  • On-demand access includes same-day deposit credit before the cut-off and next-day liquidity withdrawals.

Cons

  • The headline rate of 3.5% is variable, so the return may change.
  • Although deposits can receive same-day credit before the cut-off, withdrawals have next-day liquidity.

Ready to try StoneCastle?

Scored 9.0 / 10 by SumCue.

See alternatives

Who it suits

  • Savers who want on-demand access rather than a fixed-term account.
  • Customers who value a low minimum deposit and no monthly fee.
  • US savers comfortable with a variable headline rate.

Who should look elsewhere

  • Wise may suit savers prioritising its listed headline rate of 3.29%.
  • bunq may suit savers comparing its listed headline rate of 3.01%.
  • Finteres may suit savers wanting to compare a broader headline-rate range of 0% to 36%.

How StoneCastle compares

Where StoneCastle is available

Available
United States

Countries from the brand (Source, checked September 26, 2026)

Frequently asked questions

What rate does StoneCastle offer?+

StoneCastle's easy-access account has a headline rate of 3.5%. The rate is variable, which means the return offered on the account may change rather than remaining fixed for a stated term.

What does it cost to keep the account?+

The easy-access account has a monthly fee of $0. StoneCastle also describes its model as no monthly fee, so the headline rate is not accompanied by a recurring monthly account charge.

How much must I deposit?+

The minimum deposit for the easy-access account is $0. This makes the account accessible for customers who want to begin with a relatively small balance while retaining easy access.

How quickly can I withdraw money?+

StoneCastle provides on-demand access with next-day liquidity withdrawals. Deposits submitted before the stated cut-off can receive same-day credit, so timing may matter when adding money to the account.

Which company operates StoneCastle?+

The legal entity is StoneCastle Cash Management, LLC, and StoneCastle lists its headquarters country as US. StoneCastle was founded in 2009, giving the brand an established operating history.

How can customers contact support?+

Support is available through email and phone. These channels give customers both email and phone options, although response times are not stated in the available information.

Sources

  • keepcash.com checked September 26, 2026

    Backs: Access terms, Headline rate, Pricing model, Monthly fee, Rate type

    “Liquidity is ordinarily available on a next business day basis. Same day deposit credit and next day liquidity withdrawals are subject to a 3:00 PM ET cut-off.”

  • keepcash.com/rate-tiers checked September 26, 2026

    Backs: Minimum deposit

    “KEEP by StoneCastle Rate Tiers: $0 - $1,000,000 3.50%”

  • stonecastle.com/about checked September 26, 2026

    Backs: Founded, Legal entity

    “Founded in 2009, StoneCastle provides institutional-grade cash and savings solutions that deliver stable, diversified funding to financial institutions”

  • stonecastle.com/contact checked September 26, 2026

    Backs: Headquarters, Support channels

    “Headquarters StoneCastle 152 West 57th Street, 52nd Floor New York, NY 10019”

  • stonecastle.com/insured-deposits checked September 26, 2026

    Backs: Account kind

    “Deposits always available on demand - withdraw your funds with just a few clicks”

Compiled from 5 source pages, checked September 26, 2026. We did not open an account.

Not confirmed yet: Term, Deposit protection.

StoneCastle

Easy-access saving with a low minimum deposit and no monthly fee.

9.0/10See alternatives