There is no official study period. The GMC's PLAB pages describe the exam, not how long to prepare, and any single number you hear is someone else's story, not a rule. The useful question is how long you need, given where you are and what you can give. Here is a way to answer it.
Step 1: find out where you stand
Start with an honest baseline. PLAB 1 covers common, important and acute conditions that a doctor in their second Foundation year sees, and the long-term conditions managed in primary care. Doctors who have recently worked across general medicine usually start in a different place from doctors who have spent years in a narrow specialty. Neither is better, but the gaps are different.
A quick check across every area shows where the work is. The free readiness check on this site is one way to do that.
Step 2: decide the hours you can really give
Be realistic, not hopeful. Think about your rota, your commute, your family and the weeks when everything goes wrong. A smaller number you actually hit beats a larger one you abandon in week three. For ideas, read how to balance work with studying.
Step 3: choose a length that fits both
Put the two together. A broad start and limited weekly hours means a longer plan; a strong base and more time means a shorter one.
PLAB Vault's course runs over four months: 17 teaching weeks across medicine, acute and surgical care, women's health, child health, mental health, and primary care and professional practice, then a final week of full rehearsal exams. If you have less time, shorten the weeks you spend on areas where you are already strong rather than skipping any area, because all of them are examined.
Step 4: answer the UK way
Part of your preparation is not new medicine but UK medicine. The GMC says answers follow current UK best practice and published evidence, not local arrangements. Build in time to learn where UK guidance differs from what you do now.
Step 5: let your results confirm it
Decide your readiness from a trend, not a feeling. Look across several mixed sets of questions, and at least one full mock of 180 questions in three hours, the length of the real exam. If your scores are climbing and your weak areas are shrinking, you are close. If they are flat, extend the plan.
Practice scores from any course, including ours, are estimates and are not on the GMC's scale. Use them to compare one mock with the next.
Fit the sitting to the plan
Once you know your length, work backwards to a sitting: February, May, August or November. Leave room for the six weeks results take, and remember that your two years for PLAB 2 start on the day you sit.
Questions people ask
Is four months enough for PLAB 1?
For many doctors with a broad recent clinical base and steady weekly hours, yes. If your base is narrower or your hours are fewer, plan longer.
Can I study for PLAB 1 while working full time?
Yes. Most doctors do. The key is a daily rhythm that survives your rota.
Should I study UK guidelines or my own country's?
UK guidance. The GMC says answers follow current UK best practice, not local arrangements.
How do I know I am ready?
When your scores across several full-length mocks are steady or rising and no area is far behind the rest.