When to Send a Letter by Mail vs. Email
A decision guide for choosing between physical mail, email, and PDF attachments.
The default in modern business correspondence is email, often with a PDF attachment for the formal version. But there are still situations where a printed letter sent by mail produces an outcome that an email cannot. Knowing which is which is part of the craft of professional writing.
Send a printed letter by mail when the law or contract requires it (most formal notices, tenancy actions, certain employment communications), when the recipient explicitly prefers paper (older clients, some legal counsel, certain government offices), when the gesture is personal and the physicality of the letter carries part of the message (handwritten thank-yous, hand-delivered offers), or when you want the message preserved in a way that email is not (a letter to be read by a board, a letter for a personnel file, a letter for the historical record). Use certified mail for any letter where proof of delivery may matter later. For a more granular breakdown of the conventions discussed here, see the companion professional drafting reference we maintain alongside this guide.
Send an email — usually with a PDF attachment for the formal version — for nearly everything else. Modern business correspondence has moved decisively to email, and recipients now expect it for most professional situations. The PDF attachment matters: it preserves formatting, signals seriousness, and gives the recipient a clean copy to forward, file, or print. A letter sent only as the body of an email reads as informal even when the content is not; the PDF makes it official. Practitioners who write in regulated industries may also find our compliance-aware editorial checklist a useful next step.
The in-between case is the printed letter that is also emailed. This is the strongest signal you can send for a high-stakes message: an offer, a termination, a formal proposal, a notice with legal weight. The recipient gets the email immediately and the printed letter shortly after, and the redundancy itself communicates that the message matters.
More writing guides
- How to Format a Business Letter (Block, Modified Block, and Semi-Block) A practical guide to the three accepted business letter formats and when to use each.
- Choosing the Right Salutation for a Business Letter How to pick a salutation that lands as professional without sounding stiff or generic.
- How to End a Business Letter: Sign-offs, Signatures, and Postscripts The closing of a business letter quietly shapes how the message is remembered.
- Getting the Tone Right in a Business Letter A practical guide to matching your tone to the recipient and the moment.
- Plain Language in Business Correspondence Why plain language outperforms formal language in nearly every business letter.
- How to Cite Evidence and Attachments in a Business Letter Mention attachments and references in a way the recipient can actually use.