If you have received an envelope showing PO Box 551, Fareham, PO14 9DZ as the return address, the strongest available address data links it to Gemalto, the digital-security and payment-technology company that became part of Thales in 2019.
Current postcode data reproducing Royal Mail’s Postcode Address File lists just one address for PO14 9DZ: Gemalto, PO Box 551, Fareham, PO14 9DZ. The postcode is active and is located in Fareham, Hampshire.
That does not necessarily mean the envelope was sent directly by a company called Gemalto. Thales, which acquired Gemalto, provides payment-card personalisation, physical card issuance and delivery services for financial institutions and fintech companies. In practice, a return address belonging to a card-production or fulfilment operation can therefore appear on mail sent on behalf of another consumer-facing brand.
This distinction is the key to understanding PO Box 551 Fareham.
Who is associated with PO Box 551 Fareham?
The clearest address-level evidence comes from postcode records.
UK Postcode Check, which states that its address information incorporates Royal Mail Postcode Address File data, lists:
Gemalto
PO Box 551
Fareham
PO14 9DZ
Its postcode record says Royal Mail’s Postcode Address File contains one address at PO14 9DZ, namely the Gemalto PO Box. It also identifies the postcode as active.
Gemalto was a major digital-security business whose products and services included payment technology, identity systems and telecommunications security.
On 2 April 2019, Thales officially completed its €4.8 billion acquisition of Gemalto. Thales said Gemalto would form its Digital Identity and Security division following the transaction.
So references to both Gemalto and Thales in discussions about this address are not contradictory: Gemalto became part of Thales.
Why might a bank card come from PO Box 551 Fareham?
Payment-card fulfilment is the most useful context for people trying to identify an unexplained envelope from this address.
Thales currently describes itself as a provider of both digital and physical payment services. Its financial-services operation supports banks, card issuers and fintech companies, while its D1 platform includes physical card issuance, personalised card production, customised branding and delivery-related functions.
Thales separately offers card-delivery services involving carrier coordination, shipment administration, routing, delivery performance and other logistics.
This provides an important explanation for the return address: the company whose name is on your bank card does not necessarily have to be the company whose postal address appears on the back of the envelope.
A financial institution or fintech may manage the customer account while a specialised supplier handles card personalisation, production, packaging or dispatch.
Reports involving Curve and Wise
There is also lower-level, user-generated evidence showing how the address has appeared in practice.
The envelope-identification site Who Wrote Me documented a Curve Mastercard received in 2021 with the return address PO Box 551, Fareham, PO14 9DZ. Later reader comments on the same page reported receiving Wise cards and a Samsung Pay-related card from envelopes carrying the address.
These reports are useful clues, but they should not be treated as equivalent to official company records. In particular, a reader comment cannot establish that Wise, Curve or another financial brand owns the PO Box.
What the reports do support is the broader pattern already consistent with Thales’ documented business: the Fareham address has been seen on mail containing payment cards.
Does PO Box 551 Fareham belong to Wise or Curve?
It is more accurate to describe PO Box 551 Fareham as associated with Gemalto/Thales card operations than to label it simply a “Wise address” or “Curve address.”
The postcode record itself names Gemalto.
Curve is documented by a third-party recipient report, while Wise appears in user-submitted comments on the same site.
Those brands may use outside organisations for parts of the card-production and delivery process. The return address therefore should not be read as proof of which company operates the customer’s financial account.
If you need to know who actually sent a particular card, check the card, accompanying paperwork or the account through which it was ordered.
Is PO Box 551 Fareham a scam address?
The available evidence does not justify describing PO Box 551, Fareham, PO14 9DZ itself as a scam address.
The address is listed against Gemalto in postcode data derived from Royal Mail’s address information, and Gemalto’s parent, Thales, has a substantial, documented payment-card issuance and delivery business.
However, the existence of a legitimate return address does not prove that every piece of correspondence involving it is expected or harmless.
An unexpected financial product in your name deserves attention regardless of which return address appears on the envelope.
The UK’s Report Fraud service warns that stolen identity information can be used to open bank accounts, obtain credit cards and take out other products in another person’s name. It advises people who identify suspicious activity to contact the relevant bank or lender and check their credit records.
The FCA likewise advises consumers to treat unexpected financial communications cautiously and to verify firms using independently obtained official contact details rather than simply trusting information supplied in the communication.
What should you do if you receive an unexpected card?
The right response depends on whether you recognise the financial provider.
If you recently opened an account, requested a replacement card, joined a fintech service or ordered a new payment product, an envelope carrying PO Box 551 Fareham PO14 9DZ may simply reflect the external production and delivery process.
If you recognise the brand but were not expecting a card, check your account through the company’s official app or website.
If you have never had an account with the organisation named on the card, do not activate or use it. Contact the institution using contact information obtained independently from its official website or the FCA’s records.
For an unexplained card issued in your own name, it is also sensible to review your credit file and accounts for activity you do not recognise. Report Fraud specifically identifies newly opened accounts and credit cards as possible consequences of identity fraud.
Do not give a caller your PIN, full password or security credentials merely because they claim to be contacting you about the card. The FCA advises consumers not to disclose financial or security details to unexpected contacts without independently confirming who they are dealing with.
Why doesn’t the envelope simply show the bank’s address?
Physical payment cards pass through a more complicated supply chain than an ordinary business letter.
The institution providing your account can be responsible for the customer relationship while another specialist manages the technical and physical work involved in creating the card.
Thales’ current payment services illustrate this model. Its D1 offering covers physical card issuance, including personalised cards and delivery functions, while its card-delivery operation coordinates logistics and carriers for issuers.
As a result, the return address can identify an operational supplier rather than the brand printed on the card itself.
That is why searching only for “which bank owns PO Box 551 Fareham?” can produce misleading answers.
What does PO14 9DZ tell us?
The full postcode matters because PO Box 551 on its own is not unique internationally or even necessarily unique across postal towns.
The relevant address is:
PO Box 551
Fareham
PO14 9DZ
United Kingdom
Current postcode data places PO14 9DZ in Fareham, Hampshire, and says it remains in use. The same record identifies Gemalto as the address associated with that postcode.
For anyone researching an envelope, using the complete postcode is therefore much more reliable than searching for “PO Box 551” alone.
The practical answer
For most readers, the useful answer is straightforward:
PO Box 551 Fareham PO14 9DZ is associated in Royal Mail-derived postcode data with Gemalto. Gemalto was acquired by Thales in 2019, and Thales operates payment-card issuance and delivery services for banks, fintechs and other issuers.
That helps explain why the Fareham PO Box can appear as the return address on envelopes containing financial cards even when the customer’s actual provider has a completely different name.
Recipient reports have specifically connected the address with Curve and, less formally, Wise and other payment cards, but these reports should be understood as observations rather than proof that those brands own the PO Box.
If the card or correspondence is expected, the return address itself is not an obvious cause for alarm. If the product is completely unfamiliar or was opened in your name without your knowledge, verify it directly with the financial provider and investigate possible identity misuse.
Sources
- UK Postcode Check — “PO14 9DZ.” The page reproduces Royal Mail Postcode Address File information and lists Gemalto, PO Box 551, Fareham, PO14 9DZ as the postcode’s address. No publication date is displayed. UK Postcode Check: PO14 9DZ
- Thales — “Thales Completes Acquisition Of Gemalto To Become A Global Leader In Digital Identity And Security.” Press release dated 2 April 2019. Thales acquisition of Gemalto
- Thales — “Thales D1 Platform: modern card issuing platform.” Current product page describing physical and digital card issuance, personalisation and related services. No publication date is displayed. Thales D1 card issuing platform
- Thales — “Card Delivery Optimisation.” Current product page describing card-delivery logistics and carrier management for issuers. No publication date is displayed. Thales Card Delivery Optimisation
- Who Wrote Me — “PO Box 551, Fareham, PO14 9DZ.” Published 19 December 2021. Used only for recipient-reported examples, not as proof of ownership. Who Wrote Me: PO Box 551 Fareham
- Financial Conduct Authority — “Protect yourself from scams.” First published 8 August 2017, last updated 19 January 2026. FCA: Protect yourself from scams
- Report Fraud — “Identity fraud and identity theft.” Current UK fraud-prevention guidance on accounts or credit obtained using stolen identity information. Report Fraud: Identity fraud and identity theft