Telescopic Letter Plates
High-Performance Telescopic Letter Plates for UK Front Doors
Telescopic letter plates are the smart choice for modern front doors, offering a secure, draught-resistant, and easy-to-fit mail solution for timber, uPVC, and composite doors alike.
What Is a Telescopic Letter Plate?
A telescopic letter plate, also called a sleeved letterbox, includes an internal sleeve that joins the outer and inner flaps—making it ideal for hollow or insulated doors. It ensures no drafts, improved insulation, and a clean, professional finish across timber, uPVC, and composite setups.
Styles, Finishes & Compatibility
From classic brass effect letter plates to modern matt black and marine-grade stainless steel telescopic options, we supply letter plates in over 20 durable finishes. These are compatible with internal and external door furniture, and suitable for both replacement and retrofit use.
Whether you're searching for an adjustable letter plate for a new composite door or a replacement telescopic mail slot with integrated brushes for added draught-proofing, this range covers every scenario. Many models are fire-rated for use in flats and commercial entrances, and all are designed with UK standards in mind.
Popular Finishes and Matching Hardware
Match your new telescopic letterbox with hardware from our related collections:
We supply top brands including Carlisle Brass, Heritage Brass, Frelan Hardware, and From The Anvil.
If you can’t find the exact size or finish you’re looking for, contact us here — we’re happy to help.
- 20% off
From The Anvil
From The Anvil - Polished Chrome Traditional Letterbox
SKU: anvil-45444
Sale price £302.13 (Inc. VAT) Normal Price: £377.66 £251.78 (Ex. VAT)Unit price /Unavailable Eurospec
Eurospec - Intumescent Letterbox Assemblies 254 x 56mm - Polished Brass
SKU: cb-es300
Sale price £51.94 (Inc. VAT) Normal Price: £64.92 £43.28 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 254 x 56mm - Polished Chrome
SKU: cb-es301
Sale price £51.94 (Inc. VAT) Normal Price: £64.92 £43.28 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 254 x 56mm - Polished Gold
SKU: cb-es302
Sale price £43.68 (Inc. VAT) Normal Price: £54.60 £36.40 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 254 x 56mm SAA
SKU: cb-es303
Sale price £43.68 (Inc. VAT) Normal Price: £54.60 £36.40 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 305 x 56mm. - Polished Brass
SKU: cb-es304
Sale price £59.81 (Inc. VAT) Normal Price: £74.76 £49.84 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 305 x 56mm. - Polished Chrome
SKU: cb-es305
Sale price £59.81 (Inc. VAT) Normal Price: £74.76 £49.84 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 305 x 56mm - Polished Gold
SKU: cb-es306
Sale price £51.94 (Inc. VAT) Normal Price: £64.92 £43.28 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 305 x 56mm - SAA
SKU: cb-es307
Sale price £51.94 (Inc. VAT) Normal Price: £64.92 £43.28 (Ex. VAT)Unit price /UnavailableEurospec
Eurospec - Intumescent Letterbox Assemblies 254 x 56mm - SSS
SKU: cb-es308
Sale price £51.94 (Inc. VAT) Normal Price: £64.92 £43.28 (Ex. VAT)Unit price /UnavailableCarlisle Brass
Carlisle Brass - Sleeve Letter Plate 300 x 69mm - SAA
SKU: cb-sl1
Sale price £28.51 (Inc. VAT) Normal Price: £35.64 £23.76 (Ex. VAT)Unit price /UnavailableCarlisle Brass
Carlisle Brass - Sleeve Letter Plate 300 x 69mm - Gold Anodised Aluminium
SKU: cb-sl2
Sale price £30.05 (Inc. VAT) Normal Price: £37.56 £25.04 (Ex. VAT)Unit price /Unavailable

Why Choose a Telescopic Letter Plate?
The Ideal Draught-Proof Letterbox Solution for uPVC, Timber & Composite Doors
A telescopic letter plate is more than just a mail slot—it's a practical solution for sealing the gap between the inner and outer door surfaces, especially on uPVC and composite doors. These letter plates feature an extendable internal sleeve that ensures a snug fit across a range of door thicknesses, making them easy to retrofit without complex joinery.
Thanks to integrated brushes and optional fire-rated variants, telescopic letterboxes help to reduce draughts, improve thermal performance, and support compliance on apartment and commercial entrances. Many options are compatible with fire doors, timber doors, or replacement front doors across the UK.
We supply a wide range of architectural ironmongery to complement your letter plate installation—browse our full Door Furniture and Door Chains collections to finish the look. You’ll also find matching Escutcheons, Cylinder Pulls, and Bell Pushes to complete the front door suite.
Frequently Asked Questions
What is a telescopic letter plate?
What is a telescopic letter plate?
A telescopic letter plate has a connected inner sleeve between its flaps, sealing the door cavity and preventing draughts or water ingress.
Can I use a telescopic letter plate on a timber door?
Can I use a telescopic letter plate on a timber door?
Yes — while designed for uPVC and composite, many models are suitable for timber doors too, especially with retrofit backing plates.
Do these come in black, brass, and stainless steel finishes?
Do these come in black, brass, and stainless steel finishes?
Absolutely. We offer over 20 finish options including matt black, antique brass, polished chrome, and marine-grade stainless steel.