Every year

File your CIS monthly return

A contractor in the Construction Industry Scheme files a monthly return (CIS300) for each tax month by the 19th of the next, listing each subcontractor paid and the deduction taken: 20% for a registered subcontractor, 30% for one HMRC could not match, nothing for one with gross payment status. Fileyear works out the deductions and files the return, or a nil return when nobody was paid.

File your CIS monthly return £14.40 all in · free to prepare

Prepared for you, checked by you
Pay only when you’ve checked it
Not HMRC or Companies House

Where this sits in your company’s year

Sample year end 31 March

What’s included

Fileyear does

The deduction for each subcontractor at the rate HMRC gave
The CIS300, or a nil return
The 19th of the month deadline

You do

Enter what each subcontractor was paid and their materials
Sent to HMRC through Fileyear, with your approval, using your company’s own HMRC login

You’ll needThe company’s HMRC (Government Gateway) loginThe employer PAYE and Accounts Office references from HMRC’s letter

How it works

The month
Who was paid and how much, or that nobody was. Fileyear suggests payments from the bank lines it holds.
Check and submit
The deductions and what the company pays HMRC with its PAYE.

Deadlines and penalties

Deadlines and penalties
What	Due	If late
CIS300	By the 19th after the tax month ends (the 5th)	£100, rising to £300 or more after 2 months
Nil return	Same, unless you told HMRC you are inactive	Same
Deductions	Paid with PAYE by the 22nd	Interest

Questions directors ask

Does Fileyear give subcontractors their deduction statements?

Yes. Each subcontractor paid under deduction gets a statement (a PDF) with the payment, materials and tax deducted, to give them within 14 days of the end of the tax month.

Do I need to verify a subcontractor first?

Yes, before you first pay them (unless you paid them in this or the last two tax years). Use the free verification with Fileyear: HMRC says whether to deduct 20%, 30% or nothing.

What about materials?

The deduction is on the payment less the cost of materials the subcontractor bought for the job. Labour, plant hire and their own travel are not materials.

Guides for this filing

CIS monthly returns for contractors: deductions, statements and the 19thA company paying construction subcontractors files a CIS return by the 19th of each month, including nil months. Deduction rates, statements and late penalties.Checked 5 November 2026

Related filings