1 st

A white UPVC door letterbox with a spring-loaded aluminum flap, manufactured by Yale.

Yale UPVC Door Letterbox - White (White Surround) – uPVC & Composite Doors

2 nd

A chrome-plated Yale UPVC door letterbox with smooth round edges, featuring a spring-loaded aluminum flap.

Yale UPVC Door Letterbox - Chrome – uPVC & Composite Doors

3 rd

A gold-colored Yale UPVC door letterbox with a telescopic sleeve and spring-loaded aluminum flap, displayed against a plain background.

Yale UPVC Door Letterbox - Gold (Matt) – uPVC & Composite Doors

4 th

Avocet Premium Quality Letterplate - Affinity Range Letterbox – uPVC & Composite Doors

5 th

A black UPVC door letterbox with smooth round edges from Yale.

Yale UPVC Door Letterbox - Black – uPVC & Composite Doors

Letterboxes for uPVC & Composite Doors | Standard Sizes | Fast UK Delivery

14 products

Showing 1 - 14 of 14 products

Discover Home Secure’s Door Letterbox collection—a curated range of front-door mail solutions designed to deliver lasting performance, enhanced security, and stylish appeal for all types of doors.

Collection Highlights:

Yale Welseal uPVC Door Letterbox
Featuring sleek rounded designs with a telescopic sleeve for adjustable door thickness, spring-loaded, corrosion-resistant aluminum flaps, internal brushes to block drafts, plus quick-fit and face-fix installation options
Slimline Anti‑Vandal Letterplates
Engineered with four robust security features—blind bolts to resist external tampering, outward-facing brushes for draft control and anti-vandal protection, anti-snap flap that opens to 180°, internal water seals, ultra-flexible springs, and a scratch-concealing matte-coated frame
Avocet Affinity Letterplates
Modern contoured design that complements contemporary hardware. Fully sprung flap opens to 180°, includes dual weather seals (external and internal brush), finger slot for easy access, and is built for durability with a 50,000-cycle test and BS EN 13724:2002 compliance
Letterbox Cowl / Visor Guard
An effective internal accessory to thwart “letterbox fishing” attempts—such as retrieving keys through the mail slot. It installs easily with supplied screws and prevents intrusion while maintaining door function
Fire-Retardant Internal Letterbox Bag
A secure, elegant internal pouch that captures all types of mail and conceals it from view to deter theft. Made of self-extinguishing fabric, fits most doors, locks securely, and offers fire-resistant containment for added safety
Outdoor Metal Post Boxes
Durable freestanding mailboxes with keyed locking and outward-opening flaps for weather protection—ideal for homes where wall-mounted letterplates aren’t practical

Key Benefits:

Enhanced Security: Anti-vandal, anti-snap features protect your home from forced entry and theft.
Weather Protection: Dual seals, brush systems, and water-resistant designs help preserve energy efficiency.
Long-Term Reliability: Products tested to 50,000 cycles ensure lasting operation.
Versatility: Adjustable sizing, telescopic sleeves, and various fitting options suit a wide range of doors and needs.
Added Safety Features: Options like the fire-retardant mail bag and visor guard enhance security and peace of mind.

Replacement Letterboxes for uPVC Doors

Looking for a replacement letterbox for your uPVC or composite front door? We stock the most popular letterbox sizes and styles in the UK, including 10 inch and 12 inch models for both midrail and panel fitting.

All our uPVC door letterboxes come with sprung flaps, internal brush seals for draught exclusion, and adjustable telescopic sleeves to fit a range of door thicknesses from 20mm to 80mm. Whether your old letterbox flap has snapped, the spring has broken, or you simply want to upgrade to a more secure design, fitting a replacement takes just 10 minutes with a screwdriver.

Standard Letterbox Sizes UK

Are letterboxes a standard size? Most uPVC door letterboxes in the UK come in two standard lengths: 10 inch (approximately 265mm) and 12 inch (approximately 305mm).

The aperture — the opening through which post is delivered — is typically around 230mm to 260mm wide and 40mm to 44mm high.

The most important measurement to check before ordering is your door thickness, as this determines whether you need a midrail letterbox (for thicker sections of the door, typically 40mm to 80mm) or a panel letterbox (for thinner door panels, typically 20mm to 40mm).

For a step-by-step walkthrough, read our complete guide on how to measure a letterbox.

Letterbox Security

Your letterbox can be a security weak point if left unprotected.

Letterbox burglary — also known as key fishing — is a common technique where intruders reach through the mail slot to hook keys or manipulate locks.

We stock two simple solutions: a letterbox cowl visor guard that blocks access through the slot from the inside, and a fire-retardant letterbox bag that catches post and prevents arson attempts through the mail opening.

Both fit most uPVC and composite doors and install in minutes. Browse our full letterbox security range for more options.

Letterboxes by Brand

Yale Welseal

The most popular uPVC door letterbox in the UK. Sprung aluminium flaps, telescopic sleeve for adjustable door thickness, and internal brush seals for draught exclusion. Available in 10 inch and 12 inch sizes in multiple colour combinations.

Slimline Anti-Vandal Letterplates

Our security-focused option with blind bolts, anti-snap flap, outward-facing brushes, internal water seals, and matt anti-scratch frame. Conforms to EN 13724:2002. Ideal for high-risk properties.

Avocet Affinity Letterplates

A modern contoured design that coordinates with the Avocet Affinity door furniture
range including handles and door knockers.

Complete Your Front Door Upgrade

Replacing your letterbox? It is a great time to refresh your other door furniture too.

Browse our door knockers for classic and contemporary styles, our house numbers and letters for a polished finish, or explore our full uPVC door handles collection if your handles also need updating.

Showing 1 - 14 of 14 products