ComplaintCensus

Monzo vs Santander: most-reported complaints compared

Most-reported issues at Monzo and Santander, according to reviewers on Trustpilot — classified by our automated reader and backed by verbatim quotes from distinct reviews. This is a side-by-side of what reviewers report, not a score, rating or recommendation for either company.

Monzo

TrustScore 4.6 · 72,670 reviews on Trustpilot.

2,313 reviews analysed, 2025-03-21 to 2026-09-23.

Complaint rate (recent window): 9%

51% of negative reviews get a company reply.

Support unhelpful35%
Account/app problems34%
Support unreachable16%
Other13%
Billing errors9%
“Monzo refused to make a payment I scheduled for immediate bank transfer.”
1★ Trustpilot review, 2026-07-29

Santander

TrustScore 3.5 · 12,437 reviews on Trustpilot.

1,554 reviews analysed, 2025-02-02 to 2026-09-23.

Complaint rate (recent window): 22%

50% of negative reviews get a company reply.

Support unhelpful39%
Support unreachable36%
Account/app problems35%
Billing errors7%
Other6%
“I spent 2 hours on phone with no joy trying to unblock my card”
1★ Trustpilot review, 2026-07-22

Reported on both

Issues with an evidenced category (at least two verbatim quotes) on both sides.

IssueMonzoSantander
Support unhelpful35%39%
Account/app problems34%35%
Support unreachable16%36%
Other13%6%
Billing errors9%7%

Method: reviews are classified into a fixed complaint taxonomy by an automated reader; every category shown is backed by at least two verbatim quotes from distinct reviews. Figures are census classifications, not official statistics, and reflect what reviewers reported — not findings of wrongdoing by either company. Not affiliated with, endorsed by, or sponsored by Trustpilot A/S, Monzo or Santander.