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Posted Sat, 21 Aug 2021 16:35:08 GMT by MTay Lor
I applied to HMRC for information on making additional voluntary NI contributions, and received the information I wanted. I now want to make a payment. My letter tells me to send a cheque by post, but I understand that due to Covid this is not currently accepted. I'm happy to pay by bank transfer, but I believe I need an 18 digit reference number, and this is not identified anywhere in the letter. Can you tell me how to track it down, please, or how else I can make the payment? Thank you
Posted Tue, 24 Aug 2021 15:29:10 GMT by HMRC Admin 10

To obtain an 18 digit reference you would need to call the National Insurance Enquiries helpline on 0300 200 3500 (or +44 191 203 7010 if calling from overseas).

The line is open Monday to Friday: 8am to 6pm – closed Saturdays, Sundays and bank holidays.



Posted Mon, 31 Jan 2022 14:08:18 GMT by Dodgson1 Dodgson
Once you have the 18 digit number, can you re use this number for more payments?
Posted Wed, 02 Feb 2022 09:05:41 GMT by HMRC Admin 19

Each 18 digit ref is designed to be unique for the payment made.

You would need to contact us for a new payment reference.

National Insurance: general enquiries

Thank you.
Posted Fri, 05 Aug 2022 17:47:57 GMT by LostAtSea
This is an awkward and cumbersome way of taking contributions. Moreover, we called the telephone number you listed above and your colleagues had NO idea about this 18 digit number. A cursory online search shows others have the same issue. You really need to fix this
Posted Wed, 28 Sep 2022 12:46:02 GMT by Martyn Hulyer
the contact number for the Class 3 National Insurance reference number 0300 200 3500 does not work you wait for 55 minutes and get the music and message about tech problemsd and please wait etc, after 59 minutes i have to hang up as would have to pay for the call as i get free calls and then wait 50 mins again. So that does not work. I keep trying to log in with via gateway but to confirm my ID with 2 things I have not got a passport or other things. I have a driving licence but the paper one that does not have the expire date on it but expires when I reach 70 in 2029 so I put that date in. then askes about credit and daebet cards etc , but what ever i do it does not reconise me. so can not get on to thre website due to not reconising me and can not get through to 0300 200 3500. what do I do
Posted Sun, 09 Oct 2022 05:47:57 GMT by barry ley
Hi. I need to pay back 16 years of contributions. Do I need a separate 18 digit code for each year?
Posted Tue, 25 Oct 2022 08:40:58 GMT by HMRC Admin 10
Hi barry ley
If you are going to make a single payment for the 16 years required you will need to contact the NI Helpline for the 18 digit reference number and the correct HMRC bank details to make the payment to.
If you are not going to make the payment in one lump sum I would advise you to contact the Helpline each time you are going to make a payment as this will ensure the correct 18 digit reference number for the type of NI payment you are going to make is provided.
The NI Helpline number is 03002003500.
Posted Mon, 31 Oct 2022 14:16:12 GMT by Luke Boys
I would like to make a voluntary contribution for a gap in my National insurance years. I need my 18-digit class 3 national insurance ref. number. I have tried phoning the number provided 0300 200 3500. This number does not work, I Have NEVER spoken to a person from phoning this number ever before. Is this on purpose to provide a terrible service? Please can I just have my reference number so I can make a payment please?
Posted Mon, 07 Nov 2022 15:22:47 GMT by HMRC Admin 32

We can confirm that 0300 200 3500 is the correct number to ring when an 18 digit number is requested to make a payment of voluntary class 3 National Insurance contributions. 

You could try ringing as soon as the lines open at 8am to avoid lengthy call queues.

Alternatively, you can write to us at the address below:

PT Operations North East England
HM Revenue and Customs
United Kingdom

Thank you.
Posted Mon, 09 Jan 2023 12:04:07 GMT by rosemary Scott
Is there really no other way to get an 18 digit NI number except by calling a premium rate number? It was 5 minutes before I even got past all the recorded messages. I can do my tax return on line and you have all the data from that. If I send my request in the post as suggested in an earlier thread, what information do I need to put in the request?
Posted Tue, 10 Jan 2023 15:48:46 GMT by Michael Jowett
I needed an 18 digit Class 3 National Insurance reference number to pay for 20/21 and 21/22. After a wait of 50 mins on hold, I eventually spoke to a customer service person who was able to provide me with one. When I attempted to pay online, the number was rejected as it is not in the correct format. The exact text follows. This is 18 characters and begins with 60. For example 603490017829614130. You’ll find it on your bill. Error:Enter your Class 3 National Insurance reference number in the correct format My code is 18 characters, but does not begin with 60. I could use the reference number in a standard internet bank transfer, but I'm now cautious about this if the number is deemed incorrect, and obviously I do not want a payment to be lost in the ether... Can someone confirm the reason for the error message? If it is an HMRC website data validation error, that's fine, and I'll use a standard BACS with the reference number. I'm just concerned that I may have been given an incorrect number, and don't particularly wish to join a queue for another hour to check this. Thank you
Posted Fri, 13 Jan 2023 11:10:39 GMT by FLEUR
Hi, I am living overseas now, could you please confirm the reference number below for overseas payment is correct?there is no need for Class 3 National Insurance reference number. Reference number Use your National Insurance number followed by ‘IC’, your surname then your initial. If your bank limits you to a certain amount of characters, you should use your National Insurance number followed by ‘IC’ and as much of your surname as possible. Thank you,
Posted Mon, 16 Jan 2023 16:31:30 GMT by HMRC Admin 19
Hi Rosemary Scott,

Paying voluntary Class 3 National Insurance contributionss should only be made after you have checked with the DWP via the Future Pensions Centre (FPC) that all tax years showing a shortfall will enhance your state pension entitlement.

This is because any payment made after 5 April 2016 and that does not increase your state pension without confirmation from DWP FPC may not be refunded to you.

At the moment there is an option for customers who have a state pension forecast with less than full entitlement to be transferred either from DWP FPC to HMRC for payment information.

The quickest way is to view the information online via your Personal Tax Account (PTA).

Personal tax account: sign in or set up

The National Insurance helpline is not a premium number and is charged as a standard landline rate, the correct number to call is 0300 200 3500 and is open 8am to 6pm Monday to Friday.

If you wish to write to HMRC, you will need to include your full name, current address and date of birth, plus the nature of the enquiry to: 

Individuals Caseworker
PT Operations North East England
HM Revenue and Customs

They are currently working on post received on 12 September 2022.

Or you can view your pension forecast online here:

Check your State Pension forecast

The Future Pension Cntre contact details are here:

Contact the Future Pension Centre

We do not know the timescale for post within DWP.

Thank you.
Posted Mon, 16 Jan 2023 16:37:34 GMT by Jon Rendle
Tried three times to get through. First time got through in 40 mins and 2 minutes after speaking to the agent the line went dead. Tried two more times and was on hold for over an hour with just hold music. It shouldn't be this difficult to get your 18-digit code. Absolutely ridiculous.
Posted Mon, 16 Jan 2023 17:51:01 GMT by Philip
I have been on hold for 2 Hours 30 minutes so far, it is now 1750 hrs.......what an absolute disgraceful service!!!
Posted Tue, 17 Jan 2023 13:05:44 GMT by HMRC Admin 2
Hi Michael Jowett,

18 digit reference numbers to pay Class 3 National Insurance contributions should begin with the digits 60.

It would appear that we have given you an incorrect number. We are sorry but you will need to contact the National Insurance helpline to correct this.

Thank you.
Posted Thu, 19 Jan 2023 11:00:24 GMT by Derek Reynolds
The original response regarding same 18 digit reference for multiple one off payments appears to me to be incorrect I have today been informed the same reference number maybe used for multiple one off payments and that the number is specific to the individual and not the actual one off payment. I hope the helps others who may have the same issue.
Posted Thu, 19 Jan 2023 13:09:09 GMT by flyingbanana
I am sending the money by post, conforming to the method on the HMRC website; The last listed method is; "You can pay by sending a cheque to: HM Revenue and Customs National Insurance Contributions and Employer Office BX9 1AN Allow 3 working days for your payment to reach HMRC. If you do not have an HMRC payslip Include a note with: your name, address and phone number your Class 3 National Insurance contributions reference number (or National Insurance number) how much you’re paying the period you’re paying for"
Posted Thu, 19 Jan 2023 19:45:04 GMT by hbruce bruce
Hello, I am logged into my personal tax account online and I still cannot find this 18 digit nation insurance reference number I need to pay my national insurance (or at least check to see if I have any to pay?) please can you advise me EXACTLY where in my account I can find this number. No messages or letters are saved on my account, I am currently abroad so cannot call the helpline. Please let me know how to proceed obtaining the 18 digit reference number For the love of god. This should not be so difficult

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