Digital CIS Accountants in London: Keeps You
Compliant and Gets You the Refund You're Owed
Specialist digital accountants for CIS contractors and subcontractors. Monthly CIS
returns, deduction management, refund claims, and self-assessment.
- Making Tax Digital Ready
- Fixed Monthly Fees
- CIMA Regulated
- Serving UK Clients Nationwide
Who This Service Is For
Our CIS service is for main contractors who must register, verify subcontractors, make deductions, and file monthly CIS returns. For subcontractors who have CIS deductions made from their payments and want to ensure they reclaim everything they are owed through self-assessment.
What's Included with Our Digital CIS Accounting Service?
- WHY TDA
Why Choose TDA
FAQ
Frequently Asked Questions
The Construction Industry Scheme (CIS) is an HMRC tax scheme that requires contractors to deduct money from payments to subcontractors and pay it directly to HMRC. The deduction acts as an advance payment toward the subcontractor’s tax and National Insurance. Contractors must register with HMRC as a CIS contractor, verify each subcontractor before paying them, deduct CIS tax at the appropriate rate (0% for gross payment status, 20% for registered subcontractors, 30% for unregistered), and file a monthly CIS return (CIS300) by the 19th of the following month.
If you are a subcontractor and CIS deductions have been made from your payments, you reclaim any overpayment through your self-assessment tax return. The CIS deductions are offset against your final tax liability — if the deductions exceed what you actually owe in tax and National Insurance, HMRC refunds the difference. We calculate your exact position and ensure your self-assessment claims every pound of deduction you have suffered. CIS refunds can be substantial — running to thousands of pounds for active subcontractors.
Gross payment status allows eligible subcontractors to receive the full contract payment without any CIS deduction being made. To qualify, subcontractors must meet HMRC’s business, turnover, and compliance tests (including a clean tax compliance record for the previous 12 months). Gross payment status must be reviewed annually. If you lose it HMRC reverts you to 20% deduction rate, with a significant cash flow impact. We manage your ongoing compliance to protect your gross payment status.
If you fail to file a CIS300 return by the 19th of the month, HMRC issues an automatic penalty. The penalty is £100 for the first month, rising progressively to £200, £300, and then 5% of the CIS deductions (or £3,000, whichever is greater) for persistent non-filing. Even nil returns — where no payments were made to subcontractors in the month — must be filed to avoid penalties. We file every return on time, including nil returns where applicable.
Yes, if you are registered as a CIS contractor. Once registered, you must file a monthly CIS return for every month — even months where you made no subcontractor payments. Failing to file because you had no payments in a month still attracts penalties. If your use of subcontractors is genuinely occasional and you expect to remain registered, we recommend professional management of your monthly compliance to avoid accumulating penalties.