How to write an annotated bibliography

By Dr. Rafiq Muhammad, MD, PhD · Updated June 2026

An annotated bibliography is a list of sources where each citation is followed by a short paragraph — the annotation — that summarises the source and, usually, judges it. It’s a reference list that earns its keep: instead of just naming sources, it tells a reader (and reminds you) what each one says and why it matters.

The two kinds of annotation

• Descriptive (summary) — what the source is about and what it found. No judgement.
• Critical / analytical — the summary plus an assessment of its method, credibility, or limitations, and how it fits your project. This is what most graduate assignments want.

What each annotation should contain

1. Summary — the main argument, method, and key finding, in 1–2 sentences.
2. Assessment — is it credible? What’s the sample, the method, the limitation? How does it compare to other sources?
3. Reflection — how it informs your question: what you’ll use it for, or why you’ll set it aside.

Keep each to roughly 100–200 words — one tight paragraph per source — unless your brief says otherwise.

How it differs from a reference list — and a literature review

A reference list only names sources. An annotated bibliography describes and evaluates each one, separately. A literature review goes one step further and synthesises sources into themes and an argument. The bibliography is the useful middle step: it’s often where you do the reading and judging that the review later weaves together — pairs naturally with a synthesis matrix.