Conditional job offer from a UK defence company – Skilled Worker sponsorship and Security Clearance timeline advice

Hi everyone,

I would really appreciate some advice from anyone who has been through a similar situation.

I have recently received a conditional offer for a Business Analyst role with a large UK defence company. I am currently on a Graduate Visa which expires in October 2026, and the company is currently reviewing my immigration documents through their Global Mobility team.

The role requires a security clearance process (SC), and I am trying to understand the timeline and what normally happens in these situations.

My questions are:

1. Does the security clearance usually need to be completed before you can start working, or can you sometimes start the role while clearance is still in progress (for example, doing training, onboarding, or non-sensitive work)?
2. For people who needed Skilled Worker sponsorship, when did the employer normally start the sponsorship process?

• Before security clearance?
• After security clearance?
• After starting the job?

1. My Graduate Visa expires in October, so I am trying to understand how companies normally manage the timing between:

• conditional offer,
• pre-employment checks,
• security clearance,
• visa sponsorship.

I have not handed in my notice at my current job yet because I want everything confirmed first.

Any experiences or advice from people who have been through UK defence recruitment, SC clearance, or sponsorship would be really appreciated.

Thank you!