ComplaintCensus

efile4Biz vs boomerang carnets: most-reported complaints compared

Most-reported issues at efile4Biz and boomerang carnets, 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.

efile4Biz

TrustScore 4.7 · 12,180 reviews on Trustpilot.

324 reviews analysed, 2025-12-21 to 2026-08-26.

Complaint rate (recent window): 8%

100% of negative reviews get a company reply.

Support unreachable27%
Account/app problems26%
Support unhelpful24%
Other18%
Billing errors7%
“they do not have a customer service line you can call.”
1★ Trustpilot review, 2026-04-11

boomerang carnets

TrustScore 4.9 · 1,416 reviews on Trustpilot.

211 reviews analysed, 2018-09-03 to 2026-09-23.

Complaint rate (recent window): 2%

0% of negative reviews get a company reply.

Other38%
Support unhelpful38%
Delivery failed15%
“you failed to register us appropriately causing issues in foreign countries”
1★ Trustpilot review, 2018-11-13

Reported on both

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

Issueefile4Bizboomerang carnets
Support unhelpful24%38%
Other18%38%

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, efile4Biz or boomerang carnets.