Softwr

Accounting · head to head

Mercury vs Unit21

Mercury logo

Mercury

Accounting

Banking for startups

From
Free
Rated
-
Full reviewWebsite
Unit21 logo

Unit21

Cybersecurity

No-code fraud and AML risk operations platform for fintechs and neobanks

From
On request
Rated
-
Full reviewWebsite

The short version

  • Only Mercury has a free tier, so it costs nothing to try first.
  • Each has a real cost: Mercury treasury access requires a $250,000 balance held with Mercury; Unit21 it is built for fintech scale rather than card issuer scale, so organisations reaching very high transaction volumes generally re-evaluate against heavier platforms and face a migration.
  • They diverge on capability: Mercury covers Business checking, Unit21 covers No-code rule builder.
  • Prices and features above were last checked on 1 September 2026.

Where they differ

Only the attributes on which Mercury and Unit21 actually diverge.

Attributes where Mercury and Unit21 differ
AttributeMercuryUnit21
Starting priceFreeOn request
Pricing modelfreemiumquote
Free tierYesNo
PlatformsWeb, Ios, AndroidWeb
CategoryAccountingCybersecurity
Founded2019Unknown

Identical on both: user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Mercury

  • Business checking
  • Savings accounts
  • Virtual cards
  • Team management
  • API access
  • QuickBooks
  • Xero
  • Stripe

Only in Unit21

  • No-code rule builder
  • Case management
  • SAR filing
  • Backtesting
  • Identity and device signals
  • Data ingestion API

What people use each for

The jobs each tool is most often brought in to do.

Mercury

  • Business banking and payments for startupsnot Unit21
  • Managing treasury, invoicing and corporate cards from one accountnot Unit21

Unit21

  • A neobank whose sponsor bank requires a documented monitoring programme before it will keep the BIN sponsorshipnot Mercury
  • A crypto exchange needing SAR filing and case management without building an internal compliance engineering teamnot Mercury
  • A payments startup where the fraud lead needs to ship a new rule the same day a new attack pattern appearsnot Mercury
  • A lender consolidating fraud alerts from three point tools into one investigator queue with a single audit trailnot Mercury

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Mercury

  • Treasury access requires a $250,000 balance held with Mercury
  • Non USD international wires carry a 1% conversion fee
  • Choosing OUR wire coding, which covers intermediary bank charges, costs $15 per wire
  • ACH invoicing is $1 per transaction on Mercury Plus and only free on the $299 a month Pro plan
  • Advanced and recurring invoicing require Mercury Plus at $29.90 a month

Unit21

  • It is built for fintech scale rather than card issuer scale, so organisations reaching very high transaction volumes generally re-evaluate against heavier platforms and face a migration.
  • No-code rule authoring shifts power to the risk team, which is the point, but without governance it produces rule sprawl that nobody can explain to an examiner two years later.
  • Detection quality depends on the signals you feed it, so a thin integration produces thin results and the platform cannot compensate with proprietary consortium data the way larger vendors do.
  • Pricing is quoted by volume with an annual commitment, so a fintech whose growth stalls pays for headroom it did not use.
  • SAR filing coverage is oriented to United States FinCEN reporting, so firms filing in the United Kingdom, European Union or Asia handle those submissions outside the tool.

Pricing, plan by plan

Mercury

Free
  • Mercury (Free)Free
    • ACH payments
    • Domestic wires
    • Real-time payments
  • Mercury Plus$29.9/month
    • Invoice ACH debits
    • Recurring invoices
    • Invoicing API (500/month)
  • Mercury Pro$299/month
    • All Plus features
    • Relationship manager
    • Free ACH invoice debits

Unit21

On request
  • Unit21 Platform$undefined/year
    • Priced by monitored volume and modules, annual contract
    • Fraud, AML and case management packaged separately
    • Implementation and historical data backfill quoted with the subscription

Which should you pick?

Choose Mercury if

  • You need business checking.
  • You want to start without paying.
  • You work on Web, Ios, Android.
  • You also want savings accounts.
Mercury review

Choose Unit21 if

  • You need no-code rule builder.
  • You also want case management.
Unit21 review

Questions people ask

Is Mercury or Unit21 better?
Neither clearly leads. Mercury starts at Free and Unit21 at On request, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Mercury or Unit21?
Mercury has a free tier; the other does not. Paid plans start at Free for Mercury and On request for Unit21.
Does Mercury or Unit21 run on more platforms?
Mercury runs on Web, Ios, Android. Unit21 runs on Web.
Can I use Mercury for free?
Yes. Mercury has a free tier, so you can try it without paying. Unit21 starts at On request.
What is Mercury best used for?
Mercury is most often used for business banking and payments for startups, managing treasury, invoicing and corporate cards from one account. Of those, business banking and payments for startups and managing treasury, invoicing and corporate cards from one account are not what Unit21 is typically brought in for.
What can Mercury do that Unit21 cannot?
Mercury covers Business checking, Savings accounts, Virtual cards, Team management. Unit21 covers No-code rule builder, Case management, SAR filing, Backtesting.

Answered from the vendors’ own pages

Mercury: Is Mercury business banking free?

Mercury's base banking tier is free and includes ACH payments, domestic wire transfers, real-time payments, Bill Pay, and QuickBooks/Xero automations at no monthly cost.

Source
Unit21: Do we need engineers to run it?

Only for the initial data integration. After that the design intent is that risk and compliance staff author and deploy rules themselves.

Mercury: What does Mercury Plus add beyond the free tier?

Mercury Plus costs $29.90 per month and adds invoice ACH debits, recurring invoice capabilities, invoicing API with 500 calls per month, unlimited 1099 filings, and access to partner benefits.

Source
Unit21: Does it file SARs?

Yes, it generates and electronically files suspicious activity reports to FinCEN. Non-US regimes are not covered to the same depth.

Mercury: Does Mercury charge monthly account fees?

No, Mercury states there are no minimum account balance requirements, overdraft fees, required monthly fees, or account opening fees. The free tier includes essential business banking, with paid tiers available for additional features.

Source
Unit21: Can we test a rule before it goes live?

Yes. Backtesting against historical data to see projected alert volume is one of the more useful parts of the product, because alert volume is the real cost.

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