How to Build an NHS-Connected App in the UK — DTAC, FHIR R4 & NHS Login (2025)

£35,000–£200,000 depending on NHS API integrations. Without NHS integration: £25,000–£50,000. With NHS Login only: £35,000–£60,000. With GP Connect and NHS Spine: £60,000–£150,000. DTAC compliance adds 20–40% to base development costs.

Plan for 6–12 months from initial development to DTAC approval for a well-prepared first submission. Common delays: NHS Digital supplier onboarding (takes longer than expected), Cyber Essentials Plus external verification, DSP Toolkit completion for a new organisation, and WCAG 2.1 remediation if accessibility was not built in from the start.

If your app could influence clinical decision-making — including diagnostic support, medication management, patient monitoring, or mental health applications — a Clinical Safety Officer is required under DCB0129. For patient wellness apps with no clinical decision support element, the CSO requirement may not apply. Verify with NHS Digital for your specific app type.