Both are author-date systems, so in-text citations look alike — a surname and a year in brackets. The real difference is authority: APA is a single published standard (currently the 7th edition, with a manual you can check), while Harvard is a family of institutional variants with no governing body.
So use whichever your module specifies, and apply one variant consistently throughout.
The difference that actually matters
With APA there is a right answer and you can look it up. With Harvard there isn't one — your university publishes its own variant, and that document is the only authority your marker applies. Two Harvard guides from two UK institutions will disagree on capitalisation, italics and punctuation, and both are “correct Harvard.”
This is why generic online generators cause so much trouble: they produce a Harvard, rarely your Harvard.
Find your library's referencing guide — one PDF, usually linked from the library homepage — and work from it rather than from anything you find by searching. If it's unclear, your subject librarian will settle it in one email.
Where they typically diverge
- Author initials. APA is strict: surname then initials. Harvard variants differ, some using full first names.
- Titles. APA sentence-cases article and book titles, capitalising only the first word and proper nouns. Many Harvard variants title-case instead.
- What's italicised. Both italicise the journal or book title; the treatment of volume numbers varies.
- Multiple authors. APA has specific rules for when to use “et al.” and how many names to list first. Harvard variants set their own thresholds.
- Access dates for web sources. Most Harvard variants want one. APA 7th generally doesn't require a retrieval date for stable published content.
- What the list is called. APA says References. Harvard variants use Reference list or References, and some also expect a separate bibliography.
Which one will you be asked for?
Broadly, and with plenty of exceptions: psychology, education and the social sciences lean APA; business, law, history and the humanities more often use a Harvard variant or something discipline-specific entirely — OSCOLA for law, Vancouver for medicine, MHRA or Chicago in parts of the humanities. The module handbook is authoritative, and it can differ between two modules on the same degree.
The thing markers actually penalise
Not choosing the wrong style — you rarely get to choose. It's inconsistency: a reference list where some entries follow one pattern and some another, because they came from different generators at different times of night. Individually trivial, but across forty entries it reads as carelessness and it moves a grade band.
The practical fix is to build the list as you write rather than at the end, in one format, from one guide. More on catching errors in how to check your Harvard referencing — and if any entries came from a chatbot, verify them first: models fabricate citations.
SafeGrade checks Harvard and APA referencing, flags inconsistent formatting and uncited entries, and points at the line to fix. Never stored, never used for training.
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