UK and Ireland share history but differ on tax. UK has four brackets (0/20/40/45%) with £12,570 personal allowance. Ireland has two brackets (20/40%) plus USC (Universal Social Charge 0.5-8%) and PRSI (4%). At £50,000: UK ~£7,500 (15%), Ireland ~€11,500 (23%). UK saves £4,000. At £100,000: UK ~£27,500 (27.5%), Ireland ~€38,500 (38.5%). UK saves £11,000. UK wins at almost all income levels due to higher personal allowance and lower effective rates. Ireland's high rates kick in at €42,000 (~£36,000). But Ireland has much lower corporate tax (12.5% vs UK's 25%) attracting multinationals and tech. Dublin salaries in tech can offset tax difference. Choose UK if: you're employed, want London opportunities, or earn typical salaries. Choose Ireland if: you work at US tech companies (higher salaries), prefer Dublin lifestyle, or own a business.
Section 01
The Big Picture
Top-line rates and effective take-home for a typical earner — including income tax, social contributions, and applicable surcharges.
🇬🇧
COUNTRY A
United Kingdom
TAX RATE
0-45%
Progressive
0/20/40/45% four brackets (£12,570 personal allowance)
🇮🇪
COUNTRY B
Ireland
TAX RATE
20-40%
Two-Rate
20% (to €42,000) / 40% (above) plus USC and PRSI
TYPICAL ANNUAL DIFFERENCE
Moving from Ireland → United Kingdom at £100,000
£11,000
That's £917/month back in your pocket
Section 02
Tax Savings by Income Level
Net take-home after all income tax, social contributions, and surcharges — for a single employee with no dependents.
GROSS INCOME
🇬🇧 GB TAX
🇮🇪 IE TAX
SAVINGS
10-YEAR
£30,000
£3,500 (11.7%)
€6,200 (20.7%)
UK saves £2,700
£27,000
£50,000
£7,500 (15%)
€14,500 (29%)
UK saves £7,000
£70,000
£100,000
£27,500 (27.5%)
€43,000 (43%)
UK saves £15,500
£155,000
£150,000
£52,000 (34.7%)
€70,000 (46.7%)
UK saves £18,000
£180,000
🇬🇧
United Kingdom Pros & Cons
+ PROS
✓Higher personal allowance: £12,570 tax-free vs Ireland's €1,775 credit
✓Lower effective rates: 20% basic rate up to £50,270
✓London job market: Largest financial center in Europe
✓NHS healthcare: Free at point of use (though stretched)
✓No USC equivalent: Simpler tax structure than Ireland
− CONS
✕45% top rate: Kicks in at £125,140 (was £150K before 2023)
UK saves £3,000-18,000/year depending on income. At £50K: UK saves ~£7,000. At £100K: UK saves ~£15,500. Ireland's 40% rate plus USC (8%) plus PRSI (4%) = 52% marginal rate from €42K. UK's effective rates are much lower until very high incomes.
Q
What is Ireland's USC?
Universal Social Charge is an additional tax: 0.5% (to €12,012), 2% (to €25,760), 4% (to €70,044), 8% (above). Added to income tax 20-40%. At €100K income, USC alone is ~€6,000. This is why Ireland's effective rate is much higher than headline 20-40%.
Q
Are tech salaries higher in Ireland?
Yes, US tech companies (Google, Meta, Apple, Microsoft) pay Dublin staff well—often 20-40% above typical Irish salaries. A €120K+ tech salary is common. This can offset Ireland's higher taxes vs UK for tech workers specifically.
Q
What about the UK £100K personal allowance trap?
UK personal allowance (£12,570) is reduced £1 for every £2 earned over £100K. This creates an effective 60% marginal rate between £100-125K. At exactly £125,140, allowance is zero. This narrow band has worse effective rate than Ireland's 52%.
Q
Which is better for entrepreneurs?
Ireland for corporations (12.5% vs UK's 25%). UK for sole traders and employees (lower personal tax rates). If building a company, Ireland's corporate rate is major advantage. If taking salary, UK wins. Many founders incorporate in Ireland, live in UK.