Is it OK to quit a job after 3 months?

When it's appropriate. The role was substantially different from how it was described in interviews. The team's culture is materially toxic in ways you can document. Mental health is at genuine risk. You've been offered something dramatically better externally. Roles that meet one of these usually justify quitting; the rest are usually adjustment problems.

When to wait. Most 3-month problems are adjustment friction, not structural mismatch. New roles take 90-180 days to feel comfortable. Disappointment in week 4-12 is common and usually resolves by month 6.

CV impact. A single 3-month tenure is explainable. Two short tenures stack badly — interviewers ask why your last two roles were short. The structural cost increases with each subsequent short stint.

How to leave well. Give proper notice. Don't badmouth the company. Frame the move forward in your next interviews ('I realised within the first 90 days that the role wasn't what I thought it was; my next move was deliberate'). UK 2026 employers are more accepting of short tenures than 2010-era employers, but they still prefer a coherent narrative.

Before quitting, try this. Have a direct 1:1 with your manager about what's not working. Some 3-month problems resolve when surfaced. Many don't, but the conversation lets you leave knowing you tried.