ComplaintCensus

Fleximize vs Nucleus: most-reported complaints compared

Most-reported issues at Fleximize and Nucleus, 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.

Fleximize

TrustScore 4.9 · 1,140 reviews on Trustpilot.

226 reviews analysed, 2014-11-04 to 2026-08-28.

Complaint rate (recent window): 1%

50% of negative reviews get a company reply.

Overcharging31%
Aggressive collections23%
Support unhelpful23%
Other23%
Support unreachable15%
“They charged me 21% and in yet, they say maximum charge, 1.9% on their website.”
1★ Trustpilot review, 2026-08-13

Nucleus

TrustScore 3.8 · 1,827 reviews on Trustpilot.

135 reviews analysed, 2026-05-20 to 2026-09-25.

Complaint rate (recent window): 55%

80% of negative reviews get a company reply.

Support unhelpful60%
Support unreachable36%
Account/app problems20%
Billing errors12%
Other12%
“It has taken over two weeks at a time to correct very simple issues like cancelling a pending direct debit or correcting an incorrect NI number.”
1★ Trustpilot review, 2026-07-01

Reported on both

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

IssueFleximizeNucleus
Overcharging31%5%
Support unhelpful23%60%
Other23%12%
Support unreachable15%36%

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, Fleximize or Nucleus.