ON3 Works recruits engineers across the UK: a fully remote firm sourcing nationally rather than from one city. AI screens to a qualified shortlist in 24 to 48 hours, then a senior engineer interviews every finalist before you see them. Fees are 7% (Agentic, AI-led) or 20% (Atelier, engineer-vetted), with no deposit, so the Agentic tier often costs less than hiring in-house. You hire the engineer directly; ON3 finds and vets them.
What hiring engineers in the UK actually looks like in 2026
The UK is Europe's deepest engineering market and its most expensive. The pull right now is concentrated in AI/ML, data, cloud and DevOps, and payments infrastructure, and pay reflects scarcity. Based on ON3's index of 1.7M+ UK and Spanish technical profiles, a backend engineer in London sat around £75,000 at the mid-point of the market in 2026, with senior profiles near £95,000 and the top decile above £125,000 in cash. London is the largest single market, but 33% of our UK placements sit outside it — Manchester, Edinburgh, and remote or hybrid roles nationwide.
Speed is the other pressure. The UK average time to hire is about 4.9 weeks, and specialist tech roles often run 6 to 8 weeks in-house [StandOut CV; NatWest Mentor, 2026]. In a market where the strongest engineers are off the table within days, that gap is where good hires are lost. ON3 is built to close it: a qualified shortlist in 24 to 48 hours and a median hire in under 30 days, the same speed across every UK region.
Before you open a search, the first decision is how to run it at all. We set out the real numbers on using an agency versus hiring in-house — cost per hire, time to fill, and bad-hire risk — and on how an AI-led process compares to a traditional agency.
UK engineering pay, from ON3's dataset
Indicative annual base salary by role and seniority, drawn from ON3's UK profile index. Useful for setting a realistic offer before you open a search.
| Role (London) | Junior | Mid | Senior |
|---|---|---|---|
| Backend | £31k–48k | £64k–101k | £79k–121k |
| Full-stack | £32k–45k | £45k–75k | £70k–100k |
| ML | £38k–54k | £52k–95k | £86k–142k |
| DevOps | £26k–40k | £50k–80k | £69k–102k |
Source: ON3 Works index of 1.7M+ UK and Spanish technical profiles, refreshed daily (2026). Figures are indicative base salary; London-weighted. Independent aggregators put London backend in a similar range (Glassdoor median ~£79k, 90th percentile ~£128k).
Two tiers, one engineer-led standard
Both tiers run on the same UK-wide sourcing and the same engineer-led quality bar. A precise note on the 24 to 48 hours: that shortlist is AI-screened and qualified, not yet engineer-interviewed. In Atelier, the senior-engineer interview follows before any candidate reaches you. No deposit, billed in GBP, with a free replacement inside 90 days. Full tier detail and worked fee examples are on the pricing page.
Software, cybersecurity and deep tech
ON3 built its reputation in software and is now growing fast in cybersecurity and deep tech, including chips and HPC, which is a particular UK strength. Each role type is broken down in the profiles we cover directory. Common UK searches:
- Backend
- Full-stack
- ML / AI
- Data
- Platform
- DevOps / cloud
- Frontend / React
- Cybersecurity
- Engineering leadership
Who ON3 hires for in the UK
The pattern is two kinds of buyer. Teams tired of traditional agencies charging a fortune for work they could do themselves come to ON3 for genuinely rigorous, technical vetting: profiles that are fully checked and actually fit the brief. And teams under urgent pressure, who never used agencies because of cost, try the Agentic model at 7%. In the UK specifically, quality tends to weigh even heavier than speed.
One example: a YC-2023 company that raised a Series B in 2026 used ON3 to hire 12 technical staff, working through ON3's venture-capital channel to find qualified candidates fast. CGI, the global consultancy, uses ON3 for 50+ hires a year and operates in the UK as well as Spain.
“ON3 Works has become my favourite external recruiting partner. They're fast, efficient, and bring us candidates already vetted, qualified, and ready to hire. They've made talent search easy for me and my team.”
— Gabriel Garcia, Vice-President Consulting Services, CGI
UK hiring FAQ
How much do technical recruiters charge in the UK?+
How fast can you fill a backend engineering role in the UK?+
Do you cover roles outside London?+
What kinds of engineers do you recruit in the UK?+
Are ON3 a recruitment agency or do you employ the engineers?+
Tell us who you need to hire
Send us the role. You'll get a qualified shortlist in 24 to 48 hours, and for critical hires, a senior engineer who interviews every finalist.
Tell us who you need to hire →Sources & notes
ON3 figures (salary bands; 7%/20%, no deposit; 24 to 48h shortlist; <30-day median hire; 90.7% retention; 90-day replacement; 1.7M+ profile index; 67% of UK placements London-based; YC/Series-B and CGI references): supplied by ON3 Works. Market agency fee ranges (15–25% contingency, 25–33% retained) are typical UK published rates.
UK time to hire (~4.9 weeks; tech 6 to 8 weeks): StandOut CV; NatWest Mentor (2026). Independent salary cross-check (London backend ~£79k median, ~£128k 90th percentile): Glassdoor; IT Jobs Watch (2026).
Note: the 24 to 48h shortlist is AI-screened-qualified, not yet engineer-interviewed; the engineer vet follows in Atelier. Salary figures are indicative and should be confirmed for a specific role and location.