Attendance payment: £5,323 over nine weeks (£30,755 pro-rata).
Dates of Internship: Monday 29th June until Friday 28th August 2026
Hours of Internship: Full time (37 hours a week, Monday-Friday). For the first two weeks, you’ll need to attend 9am-5pm. After that, flexitime may be available, subject to agreement and depending on events taking place on certain days. Please note that this is an office-based role for the duration of the internship—remote or home working is not available.
About Us
GCHQ is an intelligence, cyber and security agency with a mission to keep the UK safe. We use cutting-edge technology, ingenuity and partnerships to identify, analyse and disrupt threats. Working with our intelligence partners MI5 and MI6, we protect the UK from terrorism, cyber-attacks and espionage. At GCHQ you’ll do varied and fascinating work in a supportive and inclusive environment that puts the emphasis on teamwork.
The Role
On our Maths and Cryptography Internship, you’ll work on projects which are of real, operational interest to our organisation. Throughout this nine-week paid internship you’ll work with other undergraduate students to collaboratively conduct innovative research, supported by technical experts in their fields.
GCHQ is keen to invest in enhancing your maths and programming skills. You’ll have the opportunity to work on multiple technical projects, which in the past have included:
• Assessing cryptographic algorithms
• Analysing complex data sets
• Developing new statistical tools
• Programming high performance computers
• Doing cutting-edge mathematical research.
The 2026 Maths and Cryptography Internship will run from Monday 29th June until Friday 28th August 2026. The role is based in Cheltenham. We can arrange temporary accommodation for you close to GCHQ and with other interns, which would be paid in arrears from your salary. Please consider any financial implications and practicalities before submitting an application.
About You
You need to be currently studying for an undergraduate degree (Bachelors, Integrated Masters, or equivalent) in mathematics, or a Joint Honours subject with mathematics as the main component. By the start date of the placement, you’ll have completed a minimum of two taught years of your degree (or equivalent for part-time courses) and should be on track to achieve a 2:1 qualification. Please note that the Scottish foundation year does not count towards the minimum two taught years.
You’ll already have at least an A in A-level maths (or equivalent).
We’ll look for evidence of sound mathematical grounding and ability, although we don’t require specialisation in any particular areas. Previous programming experience is useful but not essential, as training will be provided. You’ll also have a love for solving problems and an interest in developing new skills.
Training and Development
At GCHQ we’re proud of our inclusive and supportive working environment. Due to the nature of our work, the projects you’ll be working on may include technical areas where you have little existing knowledge. However, our training programme will cover all the relevant mathematical topics and programming skills required and will give you plenty of opportunities to develop. Additionally, each project will be supported by experienced members of our maths community who will provide technical expertise.
The internship will give you a unique opportunity to gain an insight into our ways of working and you’ll gain skills and experience through coaching and mentoring from our current mathematicians. A summer with us will give you a good introduction to where your career could take you, including our maths and cryptography roles.
Rewards and Benefits
You’ll receive a salary of £30,755 (pro-rata, over the nine-week internship; this equates to £5,323) plus other benefits including:
• 4.5 paid days off that you can use during the internship
• Flexible working hours for most of the summer
• Facilities such as a subsidised gym and restaurant, and on-site coffee bars.
Equal Opportunities
At GCHQ diversity and inclusion are critical to our mission. To protect the UK, we need a truly diverse workforce that reflects the society we serve. This includes diversity in every sense of the word: those with different backgrounds, ages, ethnicities, gender identities, sexual orientations, ways of thinking and those with disabilities or neurodivergent conditions. We therefore welcome and encourage applications from everyone, including those from groups that are under-represented in our workforce such as women, those from an ethnic minority background, people with disabilities and those from low socio-economic backgrounds. Find out more about our culture, working environment and diversity on our website.
We’re Disability Confident
GCHQ is proud to have achieved Leader status within the DWP’s Disability Confident scheme. This is aimed at encouraging employers to think differently about disability and take action to improve how they recruit, retain and develop disabled people. As a Disability Confident Leader, we aim to ensure that a fair and proportionate number of disabled applicants who best meet the essential minimum criteria for this position, will be offered an interview, if it is practical for us to do so. (This is known as Offer of an Interview.) To secure an interview for this role, the minimum criteria (in order of application process) are:
• Have at least a grade ‘A’ in Maths at A-Level (or equivalent)
• Be currently studying for an undergraduate degree (Bachelors, Integrated Masters, or equivalent) in mathematics, or a Joint Honours subject with mathematics as the main component
• By the start date of the placement, you must have completed a minimum of two taught years of your degree (or equivalent for part-time courses). Note that the Scottish Foundation year does not count towards the minimum two taught years
• You must be on track to achieve a 2:1 qualification at the end of your degree.
There is a wide range of extra support available throughout the recruitment process to enable you to do your best, see our website for information on reasonable adjustments we can offer.
What to Expect
Our recruitment process is fair, transparent, and based on merit. Here is a brief overview of each stage, in order:
• Initial application
• Full application
• Application form sift
• Virtual interview, consisting of:
o A short technical presentation
o Competency based questions
o Maths based questions
• Vetting (which may take 3 to 6 months to process)
Please note, you must successfully pass each stage of the process to progress to the next. Those who pass the application form sift will be given further information prior to the interview including the brief for the technical presentation and the competency questions you’ll be asked.
Before You Apply
To work at GCHQ, you need to be a British citizen or hold dual British nationality. Read about our eligibility criteria on our website.
This role requires the highest security clearance, known as Developed Vetting (DV). It’s something everyone in the UK Intelligence Community undertakes. Find out more about the vetting process on our website.
Please note we have a strict drugs policy, so once you start your application, you can’t take any recreational drugs and you’ll need to declare your previous drug usage at the relevant stage.
Before you apply, we advise you to consider setting up a separate email address for your contact with us, to ensure your personal and application correspondence remain separate. Try to avoid having identifying features in your email address, such as your first and/or surname and date of birth. This is good practice and will help you to manage your application with us more securely.
Please note, you should only launch your application from within the UK. If you are based overseas, you should wait until you visit the UK to launch an application. Applying from outside the UK will impact on our ability to progress your application. You should not discuss your application, other than with your partner or a close family member.
The Internship is based in Cheltenham. We can arrange temporary accommodation for you close to GCHQ and with other interns, but this would need to be paid in arrears from your Internship payment. Please consider any financial implications and practicalities before submitting an application.
Right to Withdraw Statement
Please be aware that we reserve the right to bring forward the closing date for this role from the original closing date once a certain number of applications have been received. Please be mindful of this and submit your application at your earliest convenience to avoid disappointment.