Professional Mail Enclosing Services
Automated folding, insertion, and sealing of your documents into quality envelopes. Choose from windowed, sealed, or branded options to suit your business needs.
Envelope Options
Choose the right envelope for your mail
DL Windowed Envelopes
220mm x 110mm
Standard business envelope with window for address display. Perfect for invoices, letters, and statements.
Features:
- Window position for standard address layout
- Fits up to 3 sheets A4 (folded twice)
- Self-seal closure
- 100gsm white paper
Best for: Invoices, statements, business letters
C5 Windowed Envelopes
229mm x 162mm
Larger envelope for A5 or folded A4 documents. Ideal for newsletters, certificates, and greetings.
Features:
- Fits A5 documents flat or A4 folded once
- Large window for visibility
- Self-seal closure
- 100gsm white paper
Best for: Newsletters, certificates, marketing materials
C4 Envelopes
324mm x 229mm
Large envelope for sending A4 documents unfolded. Perfect for documents that shouldn't be creased.
Features:
- Fits A4 documents flat (no folding)
- Available with or without window
- Peel and seal closure
- 120gsm white paper
Best for: Contracts, certificates, formal documents
How Enclosing Works
From printing to posting - fully automated
We Print Your Document
Your document is printed on high-quality paper using professional printing equipment.
Automatic Folding
Documents are precisely folded to fit the selected envelope size using automated folding equipment.
Envelope Insertion
Folded documents are automatically inserted into envelopes with address window correctly positioned.
Sealing & Posting
Envelopes are sealed and prepared for Royal Mail collection with the correct postage applied.
Professional Envelope Quality
All mailings use high-quality white envelopes with secure closures
Professional Quality
High-quality white envelopes with secure self-seal closures for all mailings
Multiple Sizes
Choose from DL, C5, or C4 envelopes to fit your document requirements
Automated Processing
Fast, accurate enclosing with automated folding and insertion equipment
Multi-Item Enclosures
Send multiple documents in a single envelope
Up to 10 Sheets
Standard letters can include up to 10 sheets of A4 paper in a single envelope
Mixed Documents
Combine different documents - invoices, terms, marketing materials - in one mailing
Selective Inserts
Add inserts to specific recipients based on your data - perfect for targeted campaigns
Why Choose Our Enclosing Service?
Fully Automated
No manual folding or stuffing. Our automated system handles everything from printing to sealing.
Cost Effective
No need to buy envelopes, folding equipment, or maintain stock. Pay only for what you send.
Professional Quality
Consistently neat folding and insertion ensures every piece of mail looks professional.
Scalable Solution
From single letters to thousands - same quality and process regardless of volume.
Frequently Asked Questions
What envelope sizes do you offer?
We offer DL (220x110mm), C5 (229x162mm), and C4 (324x229mm) envelopes. DL is our most popular for standard business mail, C5 for marketing materials, and C4 for documents that shouldn't be folded.
Can I use windowed envelopes for all documents?
Windowed envelopes work best when addresses are in the standard top-left position on your document. If addresses are elsewhere, we can use sealed envelopes and print addresses directly on them.
How many sheets can fit in one envelope?
DL envelopes accommodate up to 3 sheets of A4 (folded twice), C5 up to 6 sheets of A4 (folded once), and C4 up to 10 sheets of A4 (unfolded). Additional sheets may incur extra postage costs.
What type of envelopes do you use?
We use high-quality white envelopes with secure self-seal closures. All envelopes meet Royal Mail standards for automated processing and provide a professional appearance for your business mail.
What's the quality of the envelopes?
We use high-quality 100gsm (DL/C5) and 120gsm (C4) white envelopes with secure self-seal closures. All envelopes meet Royal Mail standards for automated processing.
Is there an extra cost for enclosing?
No, envelope insertion and folding are included in our standard letter pricing. You only pay the per-letter rate which includes printing, enclosing, and postage.
Ready for Professional Mail Enclosing?
Let us handle the folding, inserting, and sealing while you focus on your business
Related Features
Document Inserts
Add marketing materials or additional documents to your mailings
Stapling Service
Professional multi-document packages with stapling
Custom Letterheads
Maintain brand consistency with custom letterheads and backgrounds
Hybrid Mail Service
Learn about our complete print and post solution