NI Deferment

Key facts

Deferment prevents you from paying more NI than the annual maximum across multiple employments.
You can defer Class 1 NI on a second (or third) job, and Class 2/4 when also employed.
Apply using HMRC form CA72A (for Class 1) or through your Self Assessment return (Class 4).
If you overpay without deferring, you can claim a refund after the tax year ends.

What Is NI Deferment?

National Insurance deferment is an arrangement that prevents you from overpaying NI when you have multiple sources of NI-liable income. Without deferment, each employer deducts NI independently, which can result in you paying more than the annual maximum.^[1]

Deferment is relevant in two main scenarios:

Multiple employments — you have two or more PAYE jobs
Employed and self-employed — you pay Class 1 through PAYE and also owe Class 2 and Class 4 through Self Assessment

The Annual NI Maximum

There is an effective annual maximum on the amount of NI you should pay. For 2026/27, the components are:^[2]

Component	Calculation
Class 1 main rate (8%)	On earnings between £12,570 and £50,270 = up to £3,016
Class 1 additional rate (2%)	On earnings above £50,270 = uncapped
Class 4 main rate (6%)	On profits between £12,570 and £50,270 = up to £2,262
Class 4 additional rate (2%)	On profits above £50,270 = uncapped

When you have both employment and self-employment income, HMRC ensures you don’t pay more than the equivalent of 8% (or 6% for Class 4) on the band between the threshold and the Upper Earnings Limit, plus 2% on everything above.

Deferring Class 1 NI (Multiple Jobs)

If you have two or more PAYE jobs, each employer deducts Class 1 NI independently on your earnings with them. This means you could effectively pay 8% on the £12,570–£50,270 band twice.^[1]

How to Apply

Download or request form CA72A from HMRC
Complete the form, listing all your employments and expected earnings
Send it to the National Insurance Contributions Office
If approved, HMRC issues a deferment certificate
Give the certificate to your second (and any subsequent) employer
That employer then deducts NI at only 2% on all earnings above the Primary Threshold, instead of 8%

Which job do you defer? You should defer in the job where you earn less. Keep full NI deductions in your main (higher-paying) job, and defer in the second job. This ensures you build up NI correctly in your primary employment.^[1]

End-of-Year Reconciliation

After the tax year ends, HMRC reconciles your actual NI across all employments. If you still overpaid (for example, because earnings changed), you’ll receive an automatic refund. If you underpaid due to deferment, you’ll receive a bill for the balance.

Deferring Class 2 and 4 NI (Employed + Self-Employed)

If you’re both employed and self-employed, you may want to defer your Class 4 NI to avoid paying more than the annual maximum:^[3]

Step	Action
1	Your employer deducts Class 1 NI through PAYE as normal
2	On your Self Assessment return, apply to defer Class 4 NI
3	HMRC calculates your total NI liability across both Class 1 and Class 4
4	You pay only the difference (if any) through Self Assessment

Class 2 When Also Employed

Class 2 NI is a flat weekly amount (£3.65/week in 2026/27) and cannot be deferred. However, because the amount is small and it provides qualifying years for State Pension purposes, most people pay it regardless.^[3]

When Should You Apply?

Apply for deferment before the start of the tax year if possible, or as soon as you take on a second employment. Key timings:

Class 1 deferment (form CA72A) — apply before the tax year starts or within the first few weeks. HMRC typically takes 4–6 weeks to process
Class 4 deferment — apply through your Self Assessment return when you file

Don’t worry if you miss the deadline. If you don’t apply for deferment and end up overpaying, you can claim a refund after the tax year ends. It just takes longer to get your money back.^[2]

Getting a Refund Without Deferment

If you overpaid NI because you didn’t defer, you have two routes to a refund:

Automatic Refund

HMRC sometimes identifies overpayments automatically through RTI (Real Time Information) data. If so, they’ll write to you with a refund. This isn’t guaranteed, however.

Form CA8480

You can proactively claim a Class 1 NI refund using form CA8480. You’ll need:

P60s from all employers for the relevant tax year
Your National Insurance number
Details of all employments during the year

See our guide on NI Refunds & Overpayments for full details.

Special Rules for Directors

Company directors who are also employed elsewhere should be aware that directors’ NI is calculated on an annual cumulative basis (not per pay period). This affects when deferment is appropriate — speak to your accountant or contact HMRC for advice specific to your situation.^[4]

Frequently Asked Questions

What is NI deferment?

NI deferment is an arrangement where HMRC agrees to reduce or postpone your National Insurance contributions in one job or income source because you are already paying the maximum through another. It prevents you from overpaying during the year.

Who should apply for NI deferment?

You should consider deferment if you have two or more employments and your combined earnings exceed the Upper Earnings Limit (£50,270), or if you are both employed and self-employed and expect to pay more than the annual maximum.

How do I apply to defer Class 1 NI?

Complete HMRC form CA72A and send it to the National Insurance Contributions Office. If approved, HMRC will issue a deferment certificate to your second employer, who will then only deduct NI at 2% on all earnings above the Primary Threshold.

What happens if I overpay NI without deferring?

You can claim a refund after the end of the tax year using form CA8480 or through your Self Assessment return. HMRC will calculate the overpayment and issue a refund, but this can take several months.

Can I defer Class 4 NI?

Yes. If you are employed and self-employed, you can apply to defer Class 4 NI by ticking the deferment box on your Self Assessment return. HMRC will calculate the correct amount after the year ends.

Sources

Deferring National Insurance — GOV.UK
National Insurance if you have more than one job — GOV.UK
Self-employed National Insurance rates — GOV.UK
National Insurance rates and categories — GOV.UK

NI Deferment: Avoiding Overpayment