Mercury vs Brex for startups

Reviewed 2026-09-29

Short answer: Mercury as the company's primary account; Brex when employee cards, spend policies, and travel are the problem to solve.

Neither is a bank: both run accounts through partner banks and sweep deposits across program banks for FDIC coverage well past $250,000. Both open free with no monthly fee and issue a card without a personal guarantee. The difference is what each is built around: Mercury around the bank account, Brex around company spend.

Verdict

Mercury, for a startup's primary account. The free plan covers domestic ACH and wires, its paid plans are priced per company rather than per user, and it holds the Capital & Banking slot in our Founder Stack. Pick Brex if spend control is the job: expense policies, approval chains, live budgets, and travel across a growing team, or if the extra $1M of sweep coverage matters to you.

Mercury holds the Capital & Banking slot in the Founder Stack

Mercury vs Brex: side by side

Mercury vs Brex, compared
Criterion	Mercury	Brex
Company	Fintech, not a bank; banking through Choice Financial Group and Column N.A.	Checking through Column N.A.; treasury and vault by Brex Treasury LLC, a Capital One company
Free plan	$0/month: free domestic ACH and wires, USD debit card transactions, basic invoicing, bill pay	Essentials, $0/user/month: cards, bill pay, reimbursements, travel booking, accounting integrations, up to two entities
Paid plans	Plus: $29.90/month ($23.95 billed annually). Pro: $299/month ($239.90 billed annually). Priced per company	Premium: $12/user/month. Enterprise: custom pricing
What paid adds	Plus: recurring invoices, unlimited 1099 filings. Pro: a relationship manager and NetSuite categorizations	Premium: customizable expense policies, advanced approvals, live budgets, customizable ERP and HRIS integrations, multi-entity support
FDIC coverage	Up to $5M, through partner banks' sweep networks	Up to $6M through the Vault sweep; checking alone up to $250,000
Treasury	For balances over $250,000; money market funds; SIPC-covered, not FDIC-insured	Invests in a Dreyfus government money market fund
Transfers	Free domestic ACH and wires; international USD wires free, or $15 to cover intermediary fees; 1% on non-USD wires	Free same-day ACH; payments in 30+ local currencies
Card	IO credit card (Mastercard): 1.5% cashback, no personal guarantee, no annual fee	Brex card: no personal guarantee; points from 1x to 8x by category

Primary account or spend platform

Mercury is built around the company's bank account: receiving funding, paying vendors, and holding reserves. Brex is built around spend: cards, expense policies, approvals, travel, and bill pay, with a business account alongside.

They aren't strict substitutes. A company can keep its primary balance in one and issue employee cards from the other.

What the paid plans cost

Mercury charges per company, Brex per user. Mercury Plus is $29.90 a month and Pro $299 a month, or $23.95 and $239.90 billed annually, whatever the headcount. Brex Premium is listed at $12 per user per month.

At that rate, 25 Brex users cost $300 a month, about the price of Mercury Pro on monthly billing. The plans don't buy the same things: Mercury Pro adds a relationship manager and NetSuite categorizations; Brex Premium adds expense policies, approval chains, live budgets, and ERP integrations.

FDIC coverage and treasury

Mercury offers up to $5M in FDIC insurance and Brex up to $6M, both by sweeping deposits across partner banks. Brex checking on its own is covered up to $250,000; the $6M applies to its Vault.

Above those limits, both offer treasury products that invest cash in money market funds. Mercury Treasury opens to companies with more than $250,000 across their Mercury accounts and is covered by SIPC, not FDIC insurance. Brex Treasury invests in a Dreyfus government money market fund.

When Brex is the better choice

Mercury holds our banking slot. Pick Brex when:

You need expense policies, multi-step approvals, and live budgets across departments. These are on Brex Premium.
Your team travels and you want bookings paid and reconciled on company cards. Travel booking is included from Essentials.
You run several entities: Essentials covers two, Premium adds US and international multi-entity support, and Enterprise allows unlimited entities.
You want the higher sweep ceiling: $6M against Mercury's $5M.

Facts are checked against each vendor's own pages, listed below; the verdict is our opinion. Prices change, so confirm on the vendor's site. See disclosures.