What Is a Book Proposal? A Plain-English Explainer for UK Non-Fiction Authors

Most first-time non-fiction authors assume the manuscript comes first and the deal follows. In practice, publishers decide on the strength of a proposal: a document that sells an idea before it exists on the page. It is part pitch, part plan, part proof that you are the right person to write the thing. Here is what actually goes into one, and what a commissioning editor is looking for as they read.

A proposal is a business case, not a synopsis

A synopsis tells someone what happens. A proposal tells them why publishing the book makes sense. It answers three questions in order: what is this book, who will buy it, and why you? Get those three right and the rest is detail.

That is why a proposal reads more like a short report than a piece of writing. There is room for voice, and you should use it, but the structure is deliberately unglamorous. Editors pass proposals around internally: to sales, to marketing, to rights. Every section exists because somebody in that chain needs the information to argue your case when you are not in the room.

Expect to revise it. Most authors send a slightly different version to different imprints, adjusting the comparable titles and the angle depending on whether a publisher is stronger in business, cookery or narrative history.

What goes in, section by section

Lengths vary by publisher, but most UK trade proposals run to somewhere between fifteen and thirty pages, plus a sample chapter. Here is the standard shape.

Overview

Two or three pages that open with a one-line description a bookseller could repeat from memory. Something like: “A field guide to British garden birds for people who have never owned binoculars.” Follow it with a short paragraph on what the book does, a short paragraph on what makes it different, and a handful of bulleted selling points — no more than five.

Author biography and platform

Who you are, what qualifies you, and what puts you near readers. Relevant credentials, previous writing, teaching, professional memberships, a newsletter, a podcast, a course. If you have no audience yet, say what you are doing to build one rather than leaving the question hanging. Keep it to a page and link to published work so an editor can check your prose for themselves.

Market, readership and comparable titles

“Everyone who likes books” is not a market. Name your primary reader — their situation, why they would buy, where they would find the book — then a secondary readership if there is one. Say which bookshop shelf it belongs on, and whether sales are seasonal.

Then four to eight comparable titles published in the last few years, each with author, publisher, year and format. For each one, note what it did well, how yours differs, and what it suggests about the size of your market. Avoid picking books that are far bigger than yours, or ones from a decade ago. Editors read comparables as evidence, not decoration.

Contents and chapter summaries

Give the table of contents, then a paragraph or a page per chapter. Each summary should say what the chapter covers, include one specific example or case, and land on the takeaway. Vague topic lists read as though the book has not been thought through.

Sample material

Usually the introduction plus one chapter — often not chapter one, but whichever chapter best shows your voice and your method. Some publishers ask for two chapters or around 5,000 words; check their guidelines. This is the section editors read most closely, so it should be the most polished thing you have written.

Practical details and marketing

Target word count, delivery date, whether there are illustrations or photographs, and whether any quoted material needs permission. Then a realistic note on what you can do for publicity: your network, events you already run, media contacts, speaking bookings. Over-promising here is worse than a modest, specific list. If your book quotes other people’s work or uses images, sort permissions early and take professional advice where the position is unclear.

Length, tone and the details that quietly matter

Keep the document clean and plainly formatted — 12-point type, generous margins, a contents page if it runs long. Double-space sample chapters if there is any chance an editor will print them.

Write in plain sentences. Trim adjectives that do the selling for you: “brilliant”, “unique” and “essential” persuade nobody. A proposal can be dry in its market analysis and warm in its sample chapter; that contrast is normal and reads as confidence.

Six mistakes that sink a proposal

1. Claiming the book is for everyone, which reads as being for no one.
2. Choosing comparable titles that are too big, too old or barely related.
3. Chapter summaries that list subjects instead of telling a story.
4. A biography full of achievements that never mentions a reader.
5. Sending an unedited sample chapter, on the assumption the ideas will carry it.
6. Leaving out word count and delivery date, which makes the book look speculative.

Building yours without stalling

The order you write in matters more than you would think. Start with the one-line description, because everything else has to support it. Then draft the overview, since it forces you to decide what the book actually is. Chapter summaries come next, while the structure is still flexible. Comparative titles take an afternoon in a bookshop or library. Write the biography last, when you are already warmed up, and polish the sample chapter after everything else is settled.

Before you send it, try it on two readers: one who knows your subject well enough to spot gaps, and one who knows nothing about it and can tell you where they got lost. Read it aloud once; clumsy sentences declare themselves immediately.

Finally, check each publisher’s own submission guidelines, because they differ. Most large UK trade publishers will only look at non-fiction through a literary agent, and the Writers’ & Artists’ Yearbook remains the standard place to find both. Send your proposal out in small batches, keep a note of who has it and when, and expect to wait a few weeks for a reply. Then start writing the book, because the proposal is only the door.

Photo: WokinghamLibraries / Pixabay