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We make CIS Tax Returns simple

Our CIS tax return service takes away the pressure – and frustration – of filling out your own returns and gives you peace of mind that a professional is ensuring everything is correct the first time around.

It's hassle-free

Let Simplex take the hassle from your hands. We will deal with your CIS Tax Return without delay.

Speedy repayments

In a rush to receive your repayment? Not a problem, most of our refund claims are credited within two weeks.


Maximise your repayment

Maximise your tax refund by having your CIS return prepared by qualified tax and accounting professionals.

We're experts in CIS Tax Returns

Do you dread filling out your CIS return? You’re not alone. The thought of making a mistake that could lead to huge HMRC fines and threatening letters arriving in the post is more than enough to put someone off. That’s where Simplex comes into the picture.

Our CIS tax return service takes away the pressure – and frustration – of filling out your own returns and gives you peace of mind that a professional is ensuring everything is correct the first time around.

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What is a CIS Tax Return?

A CIS tax return is designed for self-employed contractors working under the Construction Industry Scheme (CIS). This could be anyone from a bricklayer, to a plumber, to an electrician.

The important difference with a CIS return is that it takes into account all of the different sites you’ve worked at over the year.

What period is covered?

All Tax returns cover the period from 6th April one year, to 5th April the next.

When is it due?

They must be received by 31st January following the Tax year.

Allowable Expenses for CIS Tax Returns

By maximising the allowable expenses claimed on your Simplex CIS Tax return, you are essentially maximising your possible Tax rebate. It is, therefore, you keep a good record of expenses over the course of the year to ensure that no expenses have been missed.


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Travelling expenses would include the following:
• Fuel
• Repairs and servicing
• Insurance
• Toll charges
• Parking costs
• Public transport, ie. Oyster card, train tickets, bus fares

If you use your own vehicle for work based travel, it might actually be more beneficial to claim the flat rate mileage allowance (45p for the first 10,000 miles and 25p thereafter). Essentially the amount of Tax relief you can claim can be greater than the actual costs incurred.

Building inspectors walking on construction site


It is quite common for contractors to supply all materials necessary for the job, but this is not always the case. In the example above of a painter, should you be required to purchase the materials yourself, then these costs are available for Tax relief. Materials would cover the raw stock required for the job.

Examples as follows:
• Bricks and cement for bricklayers
• Wood for joiners
• Paint for decorators
• Steel for welders

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Training courses

If you have had to pay for any training courses, such as gaining a CSCS card, these costs can be claimed on your CIS Tax return as allowable expenses.

Some courses and qualifications may require an annual fee or subscription. These would also be allowable expenses for the self-employed section on your Tax return.

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Other allowable expenses

Other allowable expenses would include:
• Postage and stationery costs
• Internet expenditure
• Mobile phone bills
• Laptops or computers used for the business
• Any other expenditure necessary for the job

Construction and other site workers like joiners, builders, plumbers, or groundworkers using the Construction Industry Scheme (CIS) can claim subcontractor tax refunds for travel expenses to temporary sites. The average annual rebate for CIS workers is £2,000.  Simplex will claim CIS tax back and take care of the tax return

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