Dŵr Cymru Welsh Water mailing address

To mail a letter to Dŵr Cymru Welsh Water, a water & wastewater utility serving most of Wales and parts of western England, send it to the correspondence address at Dŵr Cymru Welsh Water, Linea, Fortran Road, St. Mellons, Cardiff, CF3 0LT. Dŵr Cymru Welsh Water is the not-for-profit water and wastewater utility for most of Wales and parts of western England, owned by the Glas Cymru group with no shareholders. This is Dŵr Cymru Welsh Water's publicly listed correspondence address — for billing disputes, service requests, account closures, and formal notices. It's not the address utilities use for bill-payment remittance; use the PO Box printed on your own bill for payments. Add your return address if you'd like a reply, and confirm this address on Dŵr Cymru Welsh Water's official contact page before anything time-sensitive.

Dŵr Cymru Welsh Water — correspondence address

Dŵr Cymru Welsh Water
Linea
Fortran Road, St. Mellons
Cardiff  CF3 0LT

Written correspondence — billing disputes, service requests, account closures, and formal notices. Not the separate address used for bill-payment remittance; use the payment stub or PO Box printed on your own bill for that.

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Mail a letter to Dŵr Cymru Welsh Water

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Your name
Your return address

Dŵr Cymru Welsh WaterLineaFortran Road, St. MellonsCardiff, CF3 0LT

Your letter, printed and mailed for you.

Key facts

  • This is Dŵr Cymru Welsh Water's correspondence mailing address, taken from the utility's own contact page.
  • Dŵr Cymru Welsh Water is a water & wastewater utility serving most of Wales and parts of western England.
  • Use it for letters, disputes, service requests, and formal notices — not for bill payments, which go to a separate PO Box printed on your bill.
  • Include your account number and service address so the utility can find your file.
  • Include your return address and a reference number so the utility can respond.
  • PostPal prints your letter and mails it for you — no printer, envelope, stamps, or post office trip.

How to send your letter

  1. 1

    Decide what your letter is for

    Use this address for written correspondence — a billing dispute, a service request, an account closure, or a formal notice. If you're mailing a cheque or payment, use the remittance address printed on your own bill instead; utilities almost always route payments to a separate PO Box.

  2. 2

    Write your letter

    Include your account number, your service address (if different from your mailing address), the outcome you're looking for, and your return address so Dŵr Cymru Welsh Water can respond.

  3. 3

    Address it to the correspondence address

    First line: Dŵr Cymru Welsh Water. Next: Linea. Then the street: Fortran Road, St. Mellons. Then the city line: Cardiff CF3 0LT.

  4. 4

    Send it with PostPal

    Write or upload your letter to PostPal with the address above prefilled. We print it, add your return address, and mail it for you — no printer, envelope, stamps, or trip to the post office.

Common questions

What does Dŵr Cymru Welsh Water do?

Dŵr Cymru Welsh Water is the not-for-profit water and wastewater utility for most of Wales and parts of western England, owned by the Glas Cymru group with no shareholders. It serves most of Wales and parts of western England. The address above is its correspondence address — the right place for account letters, disputes, and formal notices.

What is Dŵr Cymru Welsh Water's mailing address?

Dŵr Cymru Welsh Water, Linea, Fortran Road, St. Mellons, Cardiff, CF3 0LT. This is Dŵr Cymru Welsh Water's publicly listed correspondence address. Confirm it on Dŵr Cymru Welsh Water's official contact page before anything time-sensitive — utilities occasionally change offices and PO Boxes.

Can I mail my bill payment to this address?

Not usually. This is a correspondence address for letters, not the payment-processing address most utilities use for mailed cheques. Use the remittance address or PO Box printed on your own bill for payments, and this address for everything else — disputes, service requests, and written notices.

How do I dispute a charge or file a complaint by mail?

Write a clear, dated letter explaining the charge or issue, include your account number and any supporting documents, state what resolution you're asking for, and include your return address. Mailing it creates a dated paper record, which can help if the dispute escalates.

How do I close or transfer my account by mail?

Include your account number, the closing/transfer date, your forwarding address, and a phone number in case Dŵr Cymru Welsh Water needs to confirm details. Most utilities also offer this online or by phone, which is often faster if you're on a tight moving deadline — mail is best for a written record or when online/phone options aren't available.

How do I mail Dŵr Cymru Welsh Water a letter without a printer?

Write or upload your letter to PostPal with the address prefilled. We print it, add your return address, and mail it for you — no printer, stamps, or post office trip needed.

Sources

Addresses verified September 2026 against official sources. Always confirm on the official site before time-sensitive filings.

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