How to Get Security Cleared – A Guide

Security clearance is an essential part of the recruitment process in a handful of industries. If you’re applying for roles that involve exposure to or work with sensitive assets, or you’re a company that handles and comes into contact with secret or top secret information, you or your employees will need an appropriate level of security clearance to be able to carry out the work.

The process of applying for security clearance and getting vetted can be very time consuming, so it’s important to understand what the process involves and how prepared you need to be to carry it out. In this guide, we explain the different types of security clearance as well as what each level involves, how long they take and how to begin each process.

What is Security Clearance?

Security clearance, or security vetting, is the process undertaken to ensure that an individual can be trusted with certain sensitive information at a certain point.

Anyone whose employment involves access to sensitive information, assets or personnel must undergo security clearance before they begin the role. The majority of jobs in the government require some level of clearance and vetting, as do roles in cyber security, defence and aerospace.

There are several different types of security clearance that are required for different kinds of jobs, and additional checks may be required at various intervals to ensure your clearance is up to date.

The reason that security clearance is required is so that sensitive assets are kept safe and the chances of a threat to their security are kept to a minimum. A vetting procedure identifies whether a person has any history, relationships, contacts or particular interests that either indicates that they themselves might be a threat or that they may be vulnerable to an outside influence and become a threat to the safety of sensitive assets.

What does security cleared mean?

If you are security cleared it means that you have undergone one or several security clearance checks and been found to have nothing that might put you at risk of compromising sensitive information. Depending on the nature of your occupation, being security cleared may just mean that you might be exposed to sensitive information on occasion that cannot be shared with others, or you may work directly with it.

What are the 5 Levels of Security Clearance?

Different types of security clearance are required for different roles, industries and scenarios. There are five main levels of security clearance in the UK, which are explained in more detail below.

Security Check (SC)

A security check (SC) is required of any individual who is either going to have substantial access to secret information or occasional, controlled access to top-secret information and assets. It is also required when an individual will be exposed to enough sensitive information to obtain knowledge of secret projects or policies, when future career progression will not be possible without this level of clearance, when they will be in a position to bring about the same degree of damage that access to this level of information could cause, or when their role requires access to levels of sensitive information from other countries or organisations.

Getting security clearance at this vetting level begins with completing the Baseline Personnel Security Standard and a security questionnaire, then involves background checks regarding previous employment, criminal and secret service records and financial history. Additional interviews may be held reviewing any concerns from financial or other background checks, and additional checks may need to be carried out on third parties identified in the security questionnaire.

It can take between one and three months for this vetting procedure to be completed, and then an individual will either be cleared or deemed a risk and not receive security clearance. This level of clearance is usually reviewed after ten years, or five years if the candidate is a non-list X contractor, but may be brought forward if a particular risk is identified.

Enhanced Security Check (eSC)

An enhanced security check (eSC) is the next step up from a security check. It is required after an SC level of clearance has been granted if a candidate is in a role where they will need uncontrolled access to secret information and occasionally, controlled access to top-secret information. Some roles also require an eSC because they involve levels of access to certain specified information systems, or are an overseas position that exposes the individual to a significant level of espionage threat

The stages involved in an enhanced security check are similar to those in a general security check: a Baseline Personnel Security Standard and a security questionnaire, background checks regarding previous employment, criminal and secret service records and financial history, and third party interviews if necessary. An interview by a trained Investigating Officer will be conducted, and all personal finances will also be reviewed before clearance is granted.

Cyber Security

Counter Terrorist Check (CTC)

A counter-terrorist check, or CTC, is a type of security clearance that is required for those who work with or close to public figures who may be perceived as valuable by terrorists, those who have access to information that may be at risk of a terrorist attack, or those who have unrestricted access to any establishment that is deemed at risk of a terrorist attack.

There are a variety of stages involved in a counter-terrorist check, beginning with the Baseline Personnel Security Standard. A candidate will then have to fill out a security questionnaire, their company records will be checked, any criminal records and security service records will be checked, and interviews may take place if any information is thought to be suspicious.

CTC policy states that this kind of security clearance check must be reviewed after ten years, or five years if the candidate is a non-list X contractor. However, reviews can be requested at any time if an individual’s circumstance or behaviour changes, and this review may be more frequent if a certain role is deemed to be more at risk of terrorist influence.

Developed Vetting (DV)

Developed vetting (DV) is one of the highest levels of security clearance and comes above both a security check and an enhanced security check. It is required for any individual whose role requires them to have frequent, uncontrolled access to top secretary information and assets. It is also required of anyone who has access to information that would cause a similar level of damage if it was compromised, or those who need access to similar kinds of information from another country or international organization.

The vetting process involved in this level of security clearance is similar to that required for an enhanced security check. A Baseline Personnel Security Standard and a security questionnaire are completed, background checks regarding previous employment, criminal and secret service records and financial history are carried out and interviews may be conducted with third parties. An in-depth interview by a trained Investigating Officer will take place, and all personal finances will also be reviewed before clearance is granted.

This level of security clearance check is reviewed at least every seven years, or every three years if the candidate is a non-list X contractor. As with other types of security clearance, this review can be made more regularly if it is deemed necessary.

Enhanced Developed Vetting (eDV)

A very small number of roles require a level of security clearance above developed vetting, known as advanced developed vetting. This has to be agreed upon in advance by the UKSV and the Cabinet Office and requires several consenting Sponsors.

The steps involved in an enhanced developed vetting security check are a DV security questionnaire, criminal record and secret service check, a financial review and credit reference, applicant, supervisor and referee interviews, checks on third parties identified in the security questionnaire and a review of all personal finances and assets.

How to Get Security Clearance

You cannot apply for security clearance yourself; it has to be requested by either an employer or a sponsor and then carried out by the United Kingdom Security Vetting unit (UKSV).

For an organisation to be able to request security checks for their employees, they must be LIST X approved and contracted to work on a specified, classified project. List X approval may also be given to companies that have already been through a detailed security vetting process and show a clear need for vetted staff or contractors.

If you are entering a role that requires security clearance, you will be notified by your future employer. It is their responsibility to organise the necessary checks and procedures to allow you the appropriate level of security clearance before you begin the role, and it is your responsibility to supply all the necessary information for these checks to take place.

As well as being responsible for organising security clearance, employers are responsible for monitoring the situations of their employees so that any changes that may require a clearance review are quickly identified.

In some scenarios, an individual may begin a role with a lower level of security clearance than needed and work on other tasks until the right level of vetting has been carried out. This usually applies in cases where developed vetting is requested, as this process can take a very long time.

Security clearance does not last forever, and regular reviews will be required if you remain in a role that exposes you to sensitive information and assets. Sometimes, the security clearance can be transferred from one role to another, making the process of starting a new job much faster.

Filling Out Questionnaire

How Long Does Security Clearance Take?

Different types of security clearance take different amounts of time to be processed and approved, so there is quite a significant range in how long it will take for a check to get completed.

Basic security clearance can take as little as two weeks if all that is required is a simple background check. However, more complex kinds of vetting will involve the candidate collecting and providing a range of personal information, as well as in-depth interviews and references from other people.

If security clearance is required for a new job then it is likely that your employer will know how long this process usually takes and will start it with enough time to remove any hold-ups. High influxes of new candidates for vetting can slow down the process, so if you are an employer it is important never to leave these checks until the last minute.

How long does SC clearance take?

A security check (SC) clearance process usually takes between 1-3 months to complete. This kind of vetting tends to take place before a candidate starts the job that the clearance is required for, so it is important to begin early so that this start date isn’t delayed.

How long does DV clearance take?

Developed vetting (DV) is a very complex process that leads to a high level of security clearance, so it takes much longer than most other kinds of vetting. On average it can take up to 9 months before full clearance is granted and usually comes after other security checks have already been carried out


Security clearance is a necessary part of many roles in several industries, and it is useful to understand the different levels of clearance and how each process takes place if you are going to be working in one. Employers in particular should ensure that they are up to date with the latest advice on clearance and have a strict process in place for vetting and reviewing their employees, as this not only keeps the company safe but also everyone who could be at risk if sensitive information was compromised.

If you’re an employer who hires security cleared engineers, developers or project managers, KO2 is the ideal recruitment partner.

Get in touch to find out more about how we can help you find the perfect candidates for your next role.

Chris Oddy

Chris Oddy

About the Author

Chris is an award-winning recruitment consultant who has specialised in the electronics and embedded systems sector since 2008. Chris is passionate about technology and customer service.


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