You’re renewing. The third party costs £456. Comprehensive wants £589.
The difference? £133 a year. Easy decision, right? Save the money.
Except here’s what nobody tells you. If you crash your car once — just once — that “saving” evaporates instantly. Along with several thousand pounds you didn’t budget for.
The question isn’t which premium costs less. It’s which option costs less when things go wrong.
Let’s run the actual numbers.
The False Economy Everyone Falls For
Picture this scenario:
You choose third party fire and theft at £456 annually. Comprehensive would have cost £589. You’re “saving” £133 every year. Feels sensible.
Then you misjudge a corner in the rain. Not badly. Just enough. Your £8,000 car hits a lamppost.
What happens with third party:
- Your car repair bill: £5,191 (UK average collision repair)
- Or if written off: £8,000 replacement
- Courtesy car while sorting it: £50/day × 10 days = £500
- Your total cost: £5,691 minimum
What happens with comprehensive:
- Your excess: £450 (£250 compulsory + £200 voluntary)
- Everything else: covered
- Your total cost: £450
The difference? £5,241.
That’s 39 years of your annual “saving” wiped out by one crash.
How Confident Are You?
Be honest. Could you drive 39 years without one at-fault incident?
No skidding on ice. No misjudged parking. No moment where you glance at your phone for two seconds. No other driver forcing you into a kerb.
87.2% of UK drivers choose comprehensive. Not because they’re wasteful. Because the maths doesn’t support gambling.
The Car Value Calculation That Actually Matters
Forget what “people like you” supposedly buy. Here’s the formula that works:
Break-even calculation:
Car Value ÷ Annual Premium Difference = Years you need accident-free
Let’s run real scenarios with UK average premiums:
| Your Car Value | Third Party (£456) | Comprehensive (£589) | You “Save” | One Crash Costs You | Break-Even Years |
| £2,000 | £456 | £589 | £133 | £2,000 | 15 years |
| £5,000 | £456 | £589 | £133 | £5,000 | 37.6 years |
| £8,000 | £456 | £589 | £133 | £8,000 | 60 years |
| £16,000 | £456 | £589 | £133 | £16,000 | 120 years |
The average used car in the UK costs £16,000. To justify third party on a car that valuable, you’d need to drive crash-free until you’re 137 years old.
Possible? Technically. Probable? No.
Check Your Own Numbers
Look up your car’s current value on AutoTrader. Be realistic — use “good condition” pricing, not “excellent.”
Got the number? Now divide it by £133.
That’s how many consecutive years you need without one mistake for third party to make financial sense.
Still feeling confident?
When Third Party Genuinely Works
The maths can favour third party. Just rarely.
You need ALL of these to be true:
✅ Car worth under £2,000
✅ You have £5,000+ in accessible savings
✅ You could replace the car tomorrow without hardship
✅ Low annual mileage (under 5,000 miles)
✅ Car not essential for work commute
✅ Low-risk area (not London with its 11.8 thefts per 1,000 people)
Miss even one? Comprehensive wins.
The Real Person This Works For
“2007 Corsa worth £1,400. Drives 3,000 miles annually for leisure. Has £7,000 emergency fund. Works from home. Lives in rural Devon.”
For this person: Third party saves £133/year. If the Corsa gets totaled, they can absorb the £1,400 loss without disrupting their life. Car is nice-to-have, not essential.
Everyone else? Different story.
The Emergency Fund Reality Check
Even if break-even maths look okay-ish, ask yourself this:
“Could I replace my car tomorrow from savings?”
Not eventually. Not by shuffling credit cards. Tomorrow. Cash. Done.
UK savings reality makes this uncomfortable:
- 39% of adults have £1,000 or less in savings
- 16% have nothing at all
- Average collision repair: £5,191
- Average total loss: £8,000-£16,000
If you have £1,500 in savings and a £7,000 car, third party isn’t “saving money.” It’s betting you can dodge probability forever while having no safety net when you lose.
The Honest Test
Open your banking app right now.
Look at immediately accessible money. Not pension. Not locked ISA you’d pay penalties to touch. Not “I could borrow from family” fantasy money. Actual cash you could spend today.
Could that number buy your current car?
If the answer is no, you’re underinsured.
When Comprehensive Is Obviously Better
For most UK drivers, comprehensive makes clear sense:
✅ Car worth over £3,000
✅ Savings under £5,000
✅ You need the car for work
✅ High mileage (over 8,000 annually)
✅ Financed or leased vehicle
✅ Live in urban area
✅ Cannot absorb sudden £5,000+ expense
The Person Who Needs Comprehensive
“2019 Focus worth £9,000. Drives 12,000 miles yearly to office. Has £2,500 in savings. Lives in Birmingham. Still paying finance on it.”
For this person: Third party “saves” £133/year. One at-fault crash costs £9,000 they don’t have. Would take 67 years accident-free to break even. Finance company requires comprehensive anyway.
The “saving” is imaginary. The risk is real.
The Hidden Costs Nobody Calculates
Third party looks cheaper until you crash. Then the costs multiply beyond just the car.
What one at-fault collision actually costs:
- Car repair/replacement: £5,191 average (or full car value if written off)
- Courtesy car hire: £50/day × 14 days = £700
- Buying replacement urgently: Overpay by £800-£1,200 (no time to negotiate)
- Emergency finance if needed: 15% APR on £5,000 = £375 interest year one
- Time off work sorting it: 2 days = £250 lost wages
- Higher premiums next year: +20-30% regardless of cover type
Real scenario with £8,000 car:
Third party holder’s crash total:
- Car: £8,000
- Hire car: £700
- Rushed replacement overpayment: £1,000
- Finance interest: £400
- Lost wages: £250
- Total: £10,350
Comprehensive holder’s crash total:
- Excess: £450
- Total: £450
That’s 78 years of the annual “saving” gone in one afternoon.
The Theft Factor
Vehicle theft adds another dimension.
London sees 11.8 thefts per 1,000 people yearly. West Midlands: 7.7 per 1,000. South Yorkshire: 8.6 per 1,000.
Average stolen vehicle value when not recovered: £20,000 (yes, thieves target expensive cars).
If you live in Manchester with a £15,000 car and third party cover, one theft wipes out 112 years of your £133 annual saving.
Third party fire and theft covers this. But only if it’s stolen or burned. If it’s crashed? You’re still paying.
Finding the Right Policy After You’ve Done the Maths
Once you know which cover level suits your actual situation, the next step is comparing providers for that level.
Premiums for identical cover vary massively between insurers. The same comprehensive policy can cost £589 at one company and £720 at another. They’re assessing your risk differently.
When comparing reliable car insurance that meets your needs, check beyond the headline premium:
The details that matter:
Compulsory excess: Usually £200-£250 but can hit £3,000
Voluntary excess: Adding £100-£500 drops premium but increases out-of-pocket cost
Courtesy car: Included or not? Worth £50/day if you need it
Windscreen cover: Separate low excess (£50-£100) or part of main excess?
Breakdown cover: Bundled or separate? Standalone costs £25-£300 yearly
The Total Cost Calculation
Don’t just chase the cheapest headline premium.
Compare: Total potential cost = Premium + Likely excess + Essential add-ons
A £520 policy with £800 total excess might cost more when you claim than a £580 policy with £300 excess.
Do the maths. Actually do it. Most people skip this and regret it later.
The Verdict
The cheapest premium rarely equals the smartest choice.
For 87.2% of UK drivers choosing comprehensive, the decision comes down to simple probability:
Can you genuinely go decades without one mistake while other drivers around you make mistakes that involve your car?
The average used car costs £16,000. Third party on that vehicle requires 120 years accident-free to break even on the £133 annual saving. Nobody lives that long.
Third party genuinely works for:
- Very cheap cars (under £2,000)
- Owned by people with substantial emergency funds (£5,000+)
- Who drive rarely in low-risk areas
That describes perhaps 5-10% of UK drivers.
Everyone else:
- Cars worth £3,000+
- Limited savings cushions
- Essential commuting
- Urban areas
Comprehensive isn’t the “expensive” option. It’s the one that prevents catastrophic expense you cannot absorb.
Choosing third party to “save” £133 while driving an £8,000 car with £1,800 in savings isn’t frugal.
It’s hoping probability makes an exception for you.
It rarely does.
References
- Association of British Insurers: UK motor insurance premium tracker (Q1-Q3 2025 data, £589 comprehensive average Q1 2025)
- ABI Claims Data: Average repair costs (£5,191), total claims paid (£11.7bn), vandalism costs (£2,786)
- ONS Financial Survey: UK household savings statistics (39% with £1,000 or less, 53% with £5,000+)
- Auto Trader: Average used car values (£16,000 median retail 2025)
- Police Crime Statistics: Regional vehicle theft rates (London 11.8 per 1,000, West Midlands 7.7, South Yorkshire 8.6)
- RAC/AA: Breakdown cover pricing (£24-£300 annually), courtesy car rental rates (£35-£75/day)
