Mercury

Mercury is the operating account of choice for US-based, venture-backed startups. It is not a bank — it is a fintech that partners with regulated banks to deliver checking, savings, credit, treasury and corporate cards through a modern software layer. For founders who value clean software over branch access, and for finance leads who want treasury, cards and payments in one place, Mercury has quietly become the default.

Best for

• US-incorporated startups, SaaS companies and venture-backed businesses.
• International founders who form a Delaware C-Corp (via Atlas, Firstbase, Clerky or similar) and need US banking.
• Finance leads who want treasury, corporate cards, invoicing and international payments on one dashboard.
• Software-native teams that value API access, granular permissions and clean approval workflows.

Not ideal for

• Cash-heavy businesses — Mercury does not accept cash deposits.
• Businesses outside the US or without a US entity — Mercury only opens accounts for US-incorporated businesses.
• Anyone who wants a single regulated bank relationship — Mercury's model is fintech-plus-partner-banks.
• Very early-stage sole traders — Mercury is aimed at incorporated businesses, not personal side projects.

Independent verdict

Mercury is the best default operating account for a US-incorporated startup. The product is genuinely one integrated stack — checking, savings, treasury, corporate cards, bill pay, and (via Mercury IO) an increasing amount of finance workflow. There is no monthly fee on the standard product, no minimum balance and no wire fees on domestic USD. For most seed and Series-A companies, Mercury replaces the combination of a legacy bank, Brex or Ramp, Bill.com and a treasury spreadsheet.

The important caveat is structural. Mercury is not a bank. Deposits sit with partner banks (historically Choice Financial Group and Evolve Bank & Trust, with expanded coverage via a broader sweep-network structure) and are eligible for FDIC insurance on a pass-through basis. That model came under real scrutiny after the Synapse / Evolve disruption in 2024. Mercury was not the party involved in the Synapse failure, but the episode is a reminder that the fintech-plus-partner-bank model has structural risks distinct from banking with a chartered institution directly.

Pricing model

Mercury (standard) has no monthly fee, no minimum balance and no domestic wire fees. International wires carry a $5 fee for USD and a 1% FX markup on non-USD wires. Mercury Plus ($35/mo) adds higher API limits, priority support and additional workflow features. Mercury Pro ($350/mo) adds dedicated onboarding, higher limits and additional controls. Mercury Treasury (for eligible balances above a threshold) offers yield through partner money-market funds. Pricing is subject to change — verify on mercury.com before committing.

Account types

Standard business checking and savings accounts, plus IO (Mercury's integrated finance workflow layer — bill pay, invoicing, expense management), Mercury Credit (charge card), Mercury Treasury (yield on idle cash via partner money-market funds and T-bills) and Mercury Venture Debt / Mercury Raise for later-stage companies.

Eligibility

Mercury is available exclusively to US-incorporated businesses (C-Corps, S-Corps, LLCs) with a US EIN and a US-based business address. Founders resident abroad can open an account if the business itself is US-incorporated (typically a Delaware C-Corp). Certain industries are restricted — cannabis, adult, gambling, money-transmission and a small list of others. Mercury's KYB is thorough — expect to provide formation documents, EIN letter, operating agreement and identity verification for all beneficial owners.

Supported countries

The business must be US-incorporated. Beneficial owners can be located in most countries worldwide, subject to Mercury's sanctions and compliance screening. This is Mercury's structural advantage over traditional US banks for international founders — Delaware incorporate + Mercury account is often the fastest legal route to US banking for a non-US founder.

Supported currencies

Accounts are USD-denominated. International wires can be sent in a wide range of currencies with a 1% FX markup relative to the mid-market rate. Mercury does not offer true multi-currency accounts — for businesses that need to hold non-USD balances, pair Mercury with Wise Business or Airwallex.

Transfers

Free ACH (same-day and standard), free domestic USD wires, and international wires with the fees above. Bulk ACH via CSV upload, recurring transfers and check-mailing are supported. Mercury also offers a fast intra-Mercury transfer between accounts.

FX pricing

1% markup on non-USD international wires. This is significantly cheaper than legacy US banks (typically 2–3%) but more expensive than dedicated FX providers like Wise Business or Airwallex for the same corridor. Mercury is not the right vehicle if FX is a core cost line in your business.

Cards

Physical and virtual debit cards on every account, with per-card controls, spending limits, category restrictions and instant issuance. Mercury Credit is a separate charge card (paid in full monthly) with 1.5% cashback on eligible spend. Corporate cards can be issued to team members with per-card policies.

ATM usage and cash deposits

Mercury does not accept cash deposits — there is no branch network and no partner cash-in network. Debit cards can be used at ATMs worldwide within Mercury's daily limits, with ATM operator fees typically not reimbursed. If cash handling is meaningful to your business, Mercury is not the right primary account.

Business features and team access

Role-based permissions (Admin, Card-only, Bookkeeper, Custom), granular action-level controls, and approval workflows for outgoing payments above configurable thresholds. Multi-signer approval, IP allowlisting, hardware-key 2FA and comprehensive audit logs are standard. Team member management is one of Mercury's strongest areas — the software is meaningfully better than any legacy bank portal.

Expense controls

Native expense management within Mercury IO — receipt capture per transaction, memo requirements, category rules, per-card spend limits and merchant-level restrictions. For pure T&E workflows, dedicated tools (Ramp, Brex, Expensify) still have deeper features, but Mercury covers the majority of SMB expense needs without a second vendor.

Invoicing

Mercury IO includes native invoicing — create, send and track invoices, with ACH pay-by-link and card acceptance (with associated processing fees). It is competent for early-stage B2B. For subscription billing, revenue recognition and complex quotes, pair Mercury with Stripe Billing.

Accounting integrations

Direct integrations with QuickBooks Online and Xero for automated transaction sync, plus a public API for custom workflows. CSV export is standard and supports every mainstream accounting product. Bill pay in Mercury IO also syncs invoices and vendor records to your accounting system.

Security

Mandatory 2FA (SMS, TOTP or hardware key), IP allowlisting, per-user permissions, action-level approval workflows and comprehensive audit logs. Mercury supports Universal 2nd Factor (U2F) hardware keys for admin roles — a materially better security posture than most legacy US banks. Payments over configurable thresholds require dual approval.

FDIC pass-through and partner-bank structure

This is the single most important thing to understand. Mercury is not a bank. Deposits are held at partner banks (historically Choice Financial Group and Evolve Bank & Trust). Because deposits are swept across a network of partner banks under a program designed for pass-through FDIC insurance, eligible deposits can be covered up to $5 million (well above the $250k single-bank FDIC limit) — assuming the pass-through insurance conditions are met. That protection is real but conditional; the 2024 Synapse / Evolve disruption showed that the fintech-plus-partner-bank model can produce operational access issues even when deposits themselves are ultimately safe. For risk-conscious finance teams: understand the model before committing operating cash.

Customer support

Email and in-app chat, with priority routing for Plus and Pro customers. Response quality is broadly considered strong within fintech-partner-bank operators. Dedicated phone support and named account managers are reserved for Mercury Pro. For most seed and Series-A companies this is a clear upgrade over a legacy bank's commercial banker — for treasury-management functions at scale, a traditional commercial bank relationship still has advantages.

Mobile and desktop experience

Desktop-first — Mercury's web dashboard is the primary interface and is genuinely well-designed. iOS and Android apps cover the essentials (balances, transactions, quick transfers, card controls, approvals) but complex actions live on the web. The overall software quality is among the strongest in the sector.

Strengths

• Best-in-class software for US startup operating accounts.
• No monthly fee, no minimum balance and free domestic wires on standard.
• Extended FDIC pass-through coverage via sweep network.
• Fast onboarding for international founders with US-incorporated entities.

Weaknesses

• Not a bank — depends on partner-bank infrastructure and pass-through insurance.
• USD-only accounts; not a fit for multi-currency operations.
• No cash deposits and no branch network.
• Restricted to US-incorporated businesses.

Alternatives worth comparing

• Relay — the closest direct competitor for US startup banking, with a similar partner-bank model and a receivables-focused workflow.
• Brex — better if corporate cards and rewards are your primary need; weaker as a full checking account.
• Revolut Business — the international-first alternative for teams operating outside the US.
• Wise Business — pair with Mercury for multi-currency receivables.

Our final take

For a US-incorporated startup that values software quality and doesn't handle cash, Mercury is the correct default. Read Mercury's own disclosures on the partner-bank structure and pass-through FDIC insurance before parking material treasury balances, and consider distributing treasury across at least one chartered-bank relationship once operating cash exceeds a few million dollars. Everything else — corporate cards, bill pay, wires, team access — Mercury already does well.