Tax Investigation Helpline

How CIS Errors Happen

Accountants can make mistakes in applying CIS rules in several ways, including:

• Failing to verify subcontractors with HMRC before making payments.
• Applying the wrong deduction rates to subcontractor payments.
• Advising contractors incorrectly on their filing obligations.
• Mishandling CIS refunds or offset claims.
• Failing to distinguish between employees and subcontractors.

These errors often leave contractors exposed to backdated liabilities and HMRC penalties, even though they relied on their accountant’s advice.

What’s at Risk CIS mistakes can have serious consequences:

• Large tax bills, covering unpaid deductions or wrongly claimed refunds.
• Penalties and interest, significantly increasing the financial burden.
• Cashflow disruption, particularly if HMRC reclaims previously refunded amounts.
• Employment status disputes, leading to PAYE and NIC liabilities.
• Reputational harm, if HMRC suspects deliberate non-compliance.

For many construction businesses, a CIS dispute can be enough to put their future at risk.

How We Help

At Tax Investigation Helpline, we specialise in supporting clients affected by CIS errors caused by bad accountancy advice. We provide:

• Independent review: We assess your CIS records and identify errors caused by poor guidance.
• HMRC representation: We manage enquiries and defend your position with HMRC.
• Correction of records: We ensure your CIS submissions are corrected and compliant moving forward.
• Negotiation: Where liabilities exist, we work to reduce penalties and agree fair repayment terms.
• Accountability: We help you take action against negligent accountants where appropriate.

Our focus is always on limiting financial damage and protecting your business.

Common Issues We See Some of the most frequent CIS problems caused by accountants include:

• Contractors failing to verify subcontractors before payment.
• Subcontractor deductions calculated incorrectly.
• Incorrect or late monthly CIS returns.
• Advising subcontractors to claim expenses they aren’t entitled to.
• Poor record-keeping guidance, leaving businesses exposed during inspections.

We’ve seen these issues many times, and we know how to put them right.

Don’t Let Bad Advice Derail Your Business If your accountant has given you poor guidance on CIS, you may feel frustrated and vulnerable, especially if HMRC is demanding repayment. But you don’t have to face this alone.

At Tax Investigation Helpline, we’ve helped contractors and subcontractors resolve costly disputes caused by negligent accountants. With our support, you can reduce liabilities, defend your position, and hold bad advisors accountable.