Backend Engineer salary in Cardiff.
Live salary data from Adzuna, calibrated against Hustle Report member submissions. Updated daily.
The 25 / 50 / 75 percentile band.
25th percentile
£58,000
Median (50th)
£75,000
Calibrated estimate
75th percentile
£100,000
Percentiles describe a snapshot of advertised salaries. Real take-home depends on tax band, pension contributions and bonuses. Hustle Report members can plug their actual numbers into the in-app calculator for a precise picture.
Backend Engineer market in Cardiff.
Backend engineering pay tracks closely with database + distributed-systems depth. Engineers comfortable with Postgres at scale, queue-based architectures and one of Go / Rust / Kotlin earn 20-35% above the headline median. AI-integration backend work (vector stores, embeddings, eval harnesses) is the fastest-growing premium segment.
Cardiff specifically: Cardiff anchors Wales' growing fintech and creative-tech market. Admiral, Hodge, Confused.com and a scaling cluster of insurtech startups produce a competitive senior-engineering market. Salaries sit ~15% below Bristol equivalents; the Welsh contractor ecosystem is small but loyal, and remote-first hiring out of London has lifted advertised rates 10-20% since 2023.
Tax snapshot · 🇬🇧 GB
£1,000 / tax year
If your gross side-hustle income exceeds £1,000 in a tax year (6 April → 5 April), you must register for Self Assessment and submit a return. Below that, the trading allowance covers you — no return, no tax. The threshold is gross revenue, not profit, so a £1,200 gross with £400 of expenses still triggers registration.
Members in this role typically add £8,400/year.
Modeled on a conservative 4 hours/week of contract work at the role's implied hourly equivalent (£42/hr). The Hustle Report Monday editorial finds the briefs and ranks them by fit so the time stays small.
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Get my salary reportCommon questions
- What is the median backend engineer salary in Cardiff?
- The median on this page is £75,000 per year from live job ads where available, otherwise a curated benchmark converted to GBP. Percentiles describe advertised base salaries, not total compensation.
- How does Cardiff compare for backend engineer pay?
- Cardiff anchors Wales' growing fintech and creative-tech market. Admiral, Hodge, Confused.com and a scaling cluster of insurtech startups produce a competitive senior-engineering market. Salaries sit ~15% below Bristol equivalents; the Welsh contractor ecosystem is small but loyal, and remote-first hiring out of London has lifted advertised rates 10-20% since 2023. Use the links below to compare the same role in other cities.
- What tax and invoicing setup matters most for backend engineer side income in Cardiff?
- Two things: (1) your country threshold and filing deadlines, and (2) clean invoices. Start with https://hustlereport.co/freelance-tax/uk and use the invoice template at https://hustlereport.co/invoice-templates/uk.
- How can a backend engineer earn more without switching jobs?
- Hustle Report members in similar roles often add £8,400 per year or more from a 4-hour-per-week contract at £42/hr equivalent. The Monday brief matches live briefs to your CV.
- How do I know what to charge for a contract in Cardiff?
- Use the rate floor for your market and skill, then sanity-check it against tax and downtime. Start at https://hustlereport.co/rates/python/uk.
- Is Hustle Report regulated financial advice?
- No. Salary pages are informational benchmarks. Hustle Report does not provide investment, tax or legal advice; speak to a qualified professional for your situation.
- Where does the live salary data come from?
- Advertised roles are pulled from Adzuna where configured for this country. Figures fall back to editorial percentile bands stored in GBP and converted with the same static FX table used across Hustle Report salary guides.