Brex vs Mercury (2026): Fees, Cards and Which Startup Account Costs Less

Mercury is the cheaper and easier account for a seed-stage startup that mainly needs banking, and Brex is the pick once the company spends through many cards and wants Capital One's balance sheet behind the card. Both base accounts cost $0 a month. Brex Premium is $12 per user per month, so a five-person team pays $60 a month, while Mercury Plus is a flat $35 a month and Mercury Pro $350. Brex asks for $50,000 in the bank or a revenue record to open a card account; Mercury asks only for a US-registered company.

Every figure below was read on the vendors' own pages on October 26, 2026: Brex pricing, Brex account requirements, the Brex business account page, the Brex corporate card page, Mercury pricing and the Mercury FAQ. The five-person scenario is ours. For each product on its own, read the Brex review and the Mercury review; this page is only the head to head.

Toolradar data: the finance tools ranking on Toolradar, the software directory we run, tracked 1,134 finance tools as of October 2026, and the median cheapest paid plan across the 305 that publish one is $39 a month. Mercury Plus sits under that median and Brex Premium's five-seat bill lands just above it. Their directory pages are Brex and Mercury.

What changed in 2026: Brex is a Capital One company

Capital One completed its acquisition of Brex on April 7, 2026, and Brex's site now describes Brex LLC as a wholly owned subsidiary of Capital One, N.A. The announcement describes a stock and cash transaction. The plan prices on this page are the ones Brex's pricing page lists today, under the Brex brand.

For a founder the ownership change cuts both ways. A bank-owned card issuer answers the "will this fintech still exist in five years" question that used to hang over corporate cards. It also means the underwriting culture of a large bank now sits behind Brex's limits, and the requirements page still reserves the right to decline an applicant who meets every stated rule. Mercury remains an independent fintech, and its site says so plainly: it is not a bank, and deposits sit at Choice Financial Group and Column N.A., both FDIC members, with up to $5 million of pass-through coverage through sweep networks.

Plans and prices side by side

The pattern is clear from the table alone. Mercury prices the company, so the bill does not move when you hire. Brex prices the seat, so the bill tracks headcount, and its free tier carries more of the spend workflow (two entities, custom rules, travel) than Mercury's free tier does.

What a five-person seed startup pays

On the free tiers both cost nothing, and on the paid tiers Brex Premium costs $60 a month against Mercury Plus at $35. The Brex figure is five seats times the list price, or $720 a year, by our arithmetic. Mercury Plus is $420 a year on monthly billing or $358.80 billed yearly, by our arithmetic on the $29.90 annual rate. Mercury Pro, which exists for companies that want a relationship manager, is $4,200 a year on monthly billing or $3,588 yearly, so it is the one plan on either side that a seed startup should not need.

Headcount changes the answer. At 10 users Brex Premium reaches $120 a month and at 20 users $240, while Mercury Plus stays at $35, so the flat fee wins as soon as the team passes three paid Brex seats. The counterpoint is that most five-person startups never need Premium: custom expense policies, review chains and ERP integrations are the features that push a company up, and a team that small runs on Essentials. Equally, Mercury's paid plans sell invoicing and finance workflow, not banking, so a startup that bills customers through Stripe rather than invoices stays on the free plan.

Payroll is where Mercury's bill can jump later. Mercury Payroll lists at $100 a month plus $50 per person paid, which is $350 a month for five people by our arithmetic, but the pricing page waives it until December 31, 2026 as a limited-time offer. Brex prints no payroll product; its Premium plan integrates with HRIS tools instead. The Mercury pricing breakdown covers every per-transaction fee that survives on the free plan, and business banking fees in 2026 sets both against traditional banks.

Who gets approved

Mercury takes any company formed in the US, including one with founders abroad; Brex underwrites a card account and wants money or revenue behind it. Mercury's FAQ says customers must be formed and registered in the United States or a US territory, with existing or planned US operations. The principal address cannot be a registered agent or a P.O. box. Founders and financial controllers can live outside the US unless their country is on Mercury's restricted list. That rule makes Mercury the usual choice for an international founder with a Delaware C corporation.

Brex's requirements page asks for a US EIN, a valid US incorporation, US operations and a US physical address. It then sorts applicants by how they pay the card. A startup that has raised funding needs a $50,000 minimum cash balance for monthly payments, possibly lower with a partner referral. A company on daily payments needs an equity investment of any amount or more than $500,000 a year in revenue. A mid-market company on monthly payments needs more than $400,000 a month in revenue, and a commercial business more than $500,000 a year. Limits are set on financial statements rather than a founder's credit score. Brex says no personal guarantee is required, and that meeting the rules does not guarantee approval.

What this means in practice: a pre-seed company with $20,000 in the bank and no investor qualifies for Mercury today and for Brex only on the daily-payment path if an investor is coming. A seed company with $1 million raised qualifies for both. Our best business bank accounts ranking covers the accounts a bootstrapped firm can open with less, and the Mercury vs Relay and Bluevine vs Mercury comparisons cover the other online accounts a bootstrapped company can open.

Yield, FDIC coverage and the cash question

Brex pays on cash from the first dollar; Mercury pays more, but only above a $250,000 balance. Brex's business account page lists a total treasury return of 3.59% for balances under $500,000, rising through 3.64%, 3.74% and 3.79% to 3.94% above $20 million. There is no minimum and withdrawals settle the same hour. Its footnote is worth reading. The figure is an annualized, compounded estimate built on a money market fund's 7-day yield plus a Brex-set additional return, the fund is not FDIC-insured, and the tier can change daily with your balance.

Mercury Treasury advertises up to 4.08%, but it is available to customers with a $250,000 Mercury balance and is offered by Mercury Advisory, an SEC-registered investment adviser, with yield subject to investment risk. A seed startup with $150,000 in the account therefore earns treasury yield at Brex and nothing at Mercury until the balance crosses the line. On insured cash the order flips: Brex's Vault program advertises up to $6 million of FDIC coverage and Mercury up to $5 million, both through sweep networks at partner banks, and both well above what a seed round needs.

Cards, rewards and foreign spend

Brex publishes a points table and a 3% FX markup cap; Mercury pays a flat 1.5% cashback and charges 3% on non-USD card spend. Brex's card page lists 7x points on rideshare, 4x on Brex prepaid travel, 3x on restaurants, 2x on software and 1x on everything else, redeemable for cash back or credits. There is no personal guarantee, and limits are set on revenue or dollars raised. It charges no foreign transaction fee and applies an FX rate markup of up to 3% when conversion is needed. Local-currency cards in 50 or more countries let a subsidiary avoid that markup.

Mercury's corporate credit card pays 1.5% cashback, and both its debit and credit cards carry a 3% currency exchange fee on non-USD transactions, which the FAQ says is not returned even if the purchase is refunded. Non-USD international wires cost 1%, and companies formed outside the US cannot use the international wire features. For a startup spending mostly on US software, the Brex 2x software category and the Mercury 1.5% rate are close; for a team with staff in Europe, Brex's local-currency cards are the real difference. The best corporate cards ranking sets both cards against Ramp and the bank-issued cards, and Ramp vs Brex is the card-only comparison.

Where each one wins

Mercury wins on cost, on access and on the banking basics. The free plan covers checking, savings, free domestic and USD international wires, invoicing, bill pay and the accounting feeds. The paid plans are flat fees, so a 20-person company pays the same as a five-person one. A founder outside the US, or a company with no investor yet, gets an account at Mercury and not a card account at Brex.

Brex wins on spend control, yield from the first dollar and anything international. Essentials includes two entities, AI-powered custom rules, travel and reimbursements at $0, Treasury pays on any balance, and the card program prints its multipliers and its FX cap. The Capital One ownership adds a bank's durability for a finance lead who has to defend the choice to a board.

Both lose to a traditional bank in one case: a business that needs cash deposits or a branch. Mercury's FAQ says it does not support cash deposits, and both are online products with partner banks holding the money.

Verdict by company type

How we computed it

The five-person bills multiply each vendor's listed monthly price by the seats or months involved: Brex Premium at $12 per user times five users, Mercury Plus and Pro at their monthly and yearly list prices times twelve. The Mercury Payroll figure uses the list price printed beside the waiver, not the waived price. Eligibility rules, yields and fees are quoted from the vendor pages linked above as read on October 26, 2026, and both vendors say meeting the stated requirements does not guarantee approval. Our editorial policy covers how reviews are produced.

FAQ

Is Brex or Mercury cheaper in 2026?

Both base accounts are $0. On paid plans Mercury Plus is $35 a month flat, while Brex Premium is $12 per user per month, so a five-person team pays Brex $60 and Mercury $35, and the gap widens with every hire. A startup that never needs expense policies or recurring invoices stays free on both.

Does Capital One own Brex now?

Yes. Capital One completed its acquisition of Brex on April 7, 2026, in a stock and cash transaction, and Brex's pages describe Brex LLC as a wholly owned subsidiary of Capital One, N.A. Brex's pricing page still sells the plans under the Brex brand.

What do I need to qualify for Brex?

A US EIN, US incorporation, US operations and a US physical address. A funded startup needs a $50,000 minimum cash balance for monthly card payments. Daily payments need an equity investment of any amount or more than $500,000 a year in revenue, and a mid-market company on monthly payments needs more than $400,000 a month in revenue, per Brex's requirements page.

Can a non-US founder open a Mercury account?

Yes, as long as the company is formed and registered in the United States or a US territory, has existing or planned US operations, and the founder does not live in a country on Mercury's restricted list. The principal address can be residential but not a registered agent or P.O. box, per Mercury's FAQ.

Which pays more on cash, Brex or Mercury?

Mercury Treasury advertises up to 4.08%, but only for customers with a $250,000 Mercury balance. Brex Treasury pays a total return of 3.59% on balances under $500,000 and up to 3.94% above $20 million with no minimum, so a smaller startup earns at Brex and nothing at Mercury until it crosses the threshold.

Does Brex or Mercury charge foreign transaction fees?

Brex charges no foreign transaction fee and applies an FX markup of up to 3% when conversion is needed, avoidable with its local-currency cards. Mercury charges a 3% currency exchange fee on non-USD debit and credit card transactions and 1% on non-USD international wires.

This page is general information, not personalized financial advice. Confirm current prices, eligibility rules, yields and card terms with Brex and Mercury before you apply.

Cite this: Finpresso, "Brex vs Mercury (2026): Fees, Cards and Which Startup Account Costs Less", November 2026.

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