You have an NS&I number, perhaps from Premium Bonds bought years ago or an ISA opened on paper, and need to check a balance or update your details. Registering for online access is different from opening a new product, which could create a separate holding rather than reveal savings you already own.
Managing NS&I savings online: register first
Register an existing holding to manage eligible NS&I products. Opening a product puts money into new savings or buys Premium Bonds; registration links eligible holdings already in your name to the Online and Phone Service.
Separate the product from the login
Premium Bonds have a holder’s number for your holding and individual Prize Bond numbers for the monthly draw. Your NS&I number is the wider online-service reference, so do not assume a Prize Bond number is your sign-in reference.
Gather the details before you start
Have your NS&I number, full legal name, date of birth, postcode, email address and mobile number ready. Use the name and address NS&I already holds, as an older account may still show a previous postcode or surname and prevent an automatic match.
NS&I may ask extra questions to confirm identity. This is part of UK anti-money laundering rules and UK data protection law, designed to stop another person taking control of your savings.
Not every NS&I holding follows the same registration path. Products already held under the Online and Phone Service are normally shown after you sign in with the matching customer record, while a new NS&I account registration is used to connect eligible NS&I holdings that are not yet visible. This does not turn every legacy product into a digital service: the Investment Account remains mainly postal, and its servicing route is different from online savings management for products such as Direct Saver, ISAs or Premium Bonds.
If a holding is absent, check the product name and the personal details on record before assuming it should appear automatically.
Register and sign in through the official route
Start at NS&I’s official website and register with details that match its records. Type the address yourself or begin at NS&I’s official website, then choose registration for the Online and Phone Service rather than a page for buying a product.
Complete the registration screen by screen
Enter your NS&I number and requested personal details carefully. A wrong date format, missing middle name or former postcode can stop the match, while repeated attempts with different details may not correct the underlying record.
Protect your sign-in details
Use your own accessible email address and mobile number, create a unique password, and sign in only through the official site. Unexpected messages requesting passwords, codes or nominated bank details may be scams, even if they use the NS&I name.
Manage NS&I products by the right channel
Use the online, phone or postal route specified for the task and product. Eligible products can often be checked online, but changes involving identity, bank details or legal authority may require a call, official form or post.
Check what your product can do online
Online access can show eligible balances, Premium Bonds prize results and payment preferences. Do not assume a holding has disappeared if it is not visible: it may be linked to old details, require identity checks or have postal-only management limits.
Your NS&I access route
Online
Balances, eligible holdings, prize checks
Phone
Access help and account queries
Use the action matrix
| Task | Usually online | May need another route |
|---|
| View eligible balances | Yes | Phone if access fails |
| Check Premium Bonds prizes | Yes | Phone for account queries |
| Correct an identity mismatch | Limited | Phone, evidence or form |
| Manage postal Investment Account | No full access | Post is the main route |
For a balance or Premium Bonds result, register through the official site first and call only if matching fails. The route changes where NS&I needs documents before altering personal, banking or authority records.
Fix missing accounts and failed NS&I access
Check NS&I’s record details before treating a holding as missing. Failed access commonly results from an old address, changed name, forgotten NS&I number or a product that cannot be fully managed online.
Check eligibility before assuming loss
Use NS&I’s official forgotten-detail or recovery route first, with old and current postcodes where relevant. If it fails, contact NS&I using the number on its website and explain that you need an existing holding checked, not a new product opened.
Know when this guide does not apply
Bereavement, powers of attorney, suspected fraud, inheritance claims and some name changes have separate NS&I processes. The Investment Account is also managed mainly by post, so it may not appear or work like newer digital products.
⚠️ This process will not restore access immediately if NS&I needs proof of identity or legal authority.
If you have forgotten your NS&I number, do not use a Premium Bonds prize number as a substitute. A Premium Bonds holder’s number identifies the holding, while individual Prize Bond numbers identify bonds in the draw and are not a reliable login credential. Start with NS&I’s official recovery or forgotten-details journey and enter your name, date of birth and both your current and previous postcode where requested.
Check old letters, statements or prize notifications for a customer reference. If the online check cannot match you, contact NS&I through the details on its official website and ask for help tracing an existing holding rather than attempting repeated registrations.
Questions & answers
How do I register for an NS&I online account?
Register through the official NS&I website with your NS&I number and personal details exactly as NS&I holds them. It links eligible existing products; it does not open a new account or buy Premium Bonds.
How do I log in to NS&I Premium Bonds?
Sign in through NS&I’s official website using your registered details. Once linked, eligible Premium Bonds holdings normally allow prize checks and balance viewing.
Why can’t I find my NS&I account online?
Your name, date of birth or address may not match NS&I’s record, or the product may have postal-only limits. Use the official recovery route before concluding that the account has gone.
Can I change my nominated bank account online?
Some changes may be available online, but NS&I can require additional checks by phone or form. Follow the route shown for your product and specific request.
Are Premium Bonds prizes taxable?
Premium Bonds prizes are tax-free in the United Kingdom. They are prize payments rather than savings interest and are not guaranteed in the monthly draw.
Use the right NS&I route today
Register once using matching records, then manage every eligible holding through its stated channel. Start from NS&I’s official website, keep your NS&I number secure, and stop if a page or message seems unexpected. A failed match or postal-only product does not mean your savings have disappeared.
Learn more
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