A query letter is the single most important page most writers will ever write, and it is also the most misunderstood. It is not a plot summary, not a cover letter, and not a plea. It is a short business letter whose only job is to make an agent want to read your sample pages. Get it right and the door opens; get it wrong and the manuscript never gets read.

Keep the letter to one page, about 250 to 350 words. Open with your story, not yourself: who the main character is, what they want, what stands in the way, and what they stand to lose. Think of it as back-cover copy with facts attached. Then add the title, genre, word count, and two or three recent comparable titles. Finish with a short bio of two to four sentences and a polite close.

Personalize the opening line for each agent. Mention a book they represented that you admire, or reference something from their wish list that aligns with your work. Agents can tell instantly when a letter is mass-mailed, and a genuine personal touch signals that you have done your research. Keep it to one or two sentences; the letter is about your book, not the agent.

The most common mistakes are easy to avoid. Sending before the manuscript is finished. Querying the wrong genre. Including spoilers in the pitch, or withholding them in the synopsis, which is a separate document. Writing a bio that lists unrelated achievements instead of relevant credits, awards, or experience connected to the book. And sending a letter over 400 words, which signals that the writer cannot edit.

Send queries in batches of eight to twelve agents at a time. Use QueryTracker, Publishers Marketplace, and Manuscript Wish List to find agents actively seeking your genre, and check their recent sales. If your first batch yields nothing but form rejections, revise the query or your opening pages before sending the next batch. Most authors go through ten or twenty drafts of the letter before it works.

Before you press send, run this checklist: one page, under 350 words, hook in the first paragraph, metadata and comps included, bio relevant to this book, and the correct submission method for that agency. Then send it and start writing the next book. Querying takes months, and the best use of that time is new work.

Understanding how agents read queries changes how you write one. Most agents spend sixty to ninety seconds on a first read, scanning the hook, the metadata, and the first page before deciding. They are not reading for literary merit at this stage; they are reading for a clear premise, a character with a problem, and evidence that the writer can finish a book. A query that buries the premise in the third paragraph or spends half its length on the writer's biography is usually rejected before the sample pages are ever opened. This is why the opening sentence matters more than any other line in the letter.

It also helps to know what happens after a yes. If an agent requests the full manuscript, they will read it over days or weeks, and they may ask for revisions before offering representation. If they offer, you can and should talk to their other clients, ask about their communication style, and check their recent sales. Signing with an agent is a business partnership, not a prize, and the writers who treat it that way end up happier. A query letter is the first step in that professional relationship, so write it the way you would write to a future colleague: clearly, briefly, and with respect for their time.