Agile business cases and digital spend controls in 2026

Agile delivery fits a government business case when you fund the work in stages and update the case as the team learns, and HM Treasury’s guidance allows for both. The digital and technology spend controls no longer apply. The government replaced them on 1st April 2026, and departments now approve most of their own digital spending.

What changed on 1st April 2026

Until 31st March 2026, a department had to get central approval for digital and technology spending above set thresholds. The Government Digital Service (GDS) now states in the Service Manual that the controls were replaced on 1st April 2026 and that central government departments make most of these decisions themselves.

The detail is in the Digital Assurance Playbook, published on the same day. A sponsor should know three things from it.

• Your department runs its own approvals, and each department designs its own process. Find yours by searching your intranet for “Digital and Technology Assurance”, the phrase every department was asked to use.
• HM Treasury requires every organisation to keep a pipeline, which is a list of planned digital spending, and to share it. Anything with a whole life cost above £5 million, excluding VAT, must be on it. Early ideas should go on as soon as you know about them.
• Assurance comes first. Under the playbook, assurance must take place before any procurement or discovery work starts, and your department’s own assurers carry out most of it.

When you still need HM Treasury

You need HM Treasury approval in two cases. The first is spending above your department’s Delegated Authority Limit, the amount HM Treasury lets it approve on its own. The second is a proposal that HM Treasury judges novel, contentious or repercussive. GDS gives an example of a novel proposal that may apply to you: using artificial intelligence when your department has no internal expertise in it.

HM Treasury approves either at desk level, which is the normal route for spending above the limit, or through a Treasury Approval Process panel, where the Chief Secretary to the Treasury gives the decision. GDS supports your department’s assurers with novel, complex and high-risk proposals, including anything that needs HM Treasury approval.

What HM Treasury says about agile business cases

The document to read is HM Treasury’s clarification of business case guidance for agile digital and IT projects. These are its main points.

• A department can adapt the classic three stages of strategic outline case, outline business case and full business case. HM Treasury recommends a programme business case, with a light-touch outline case for the larger projects inside it.
• Discovery and alpha, the research and prototype phases, count as initial research. HM Treasury normally lets a department spend up to £750,000 on them from its own budget before the fuller case is written.
• A project that costs more than £10 million over its whole life, or that puts the programme at significant risk, goes to HM Treasury. Approval follows the monitoring and approval points agreed in the programme business case.
• HM Treasury will generally release funding in tranches, tied to delivery milestones or to a period such as every six months.
• At reviews, HM Treasury asks departments to demonstrate the working service and bring the team’s own records in place of long technical documents.

HM Treasury last updated that page on 28th August 2024, and it still describes Cabinet Office spend control steps that the government replaced on 1st April 2026. Read it for how to shape the case, and ask your HM Treasury spending team which of its steps and figures still apply. The National Infrastructure and Service Transformation Authority (NISTA) also sends you to your HM Treasury spending team in its guide to assuring agile delivery, updated in August 2026, because the requirements vary by department and by the size of the programme.

How to make the case for work nobody can plan in full

A business case for new digital work rests on things nobody knows yet, such as what users will do and what the old systems will allow. So write the case to be updated. Ask for money one phase at a time. State what the team will have learned by the end of the phase and what evidence you will bring back. NISTA expects a programme business case for agile work to be updated regularly and gives every six months as an example.

When the case has a date in it, give the date as a forecast with odds worked out from what the team has delivered so far, such as “an 85% chance by 6th October”, and state what is out of scope. An approver can hold you to that. Our guide to reading a delivery forecast explains the method, and the guide to the SRO’s role covers the governance around it.

We work through boards, assurance and spending approvals with SCS and G6 leaders on our one-day Agile Leadership programme.

What to do next

Search your intranet for “Digital and Technology Assurance” and read your department’s process. Check that your programme is on the pipeline. Then speak to your assurance team and your HM Treasury spending team before discovery starts.