Introduction
When it comes to keeping your garden looking pristine, the type of lawnmower you choose can make all the difference. Two of the most popular options are cordless electric and petrol-powered mowers, each with distinct advantages and drawbacks. Whether you’re a first-time buyer or looking to upgrade from an old machine, understanding the differences between these two types is crucial. This guide breaks down cordless and petrol mowers side by side, examining everything from power and performance to cost and environmental impact. By the end, you’ll know exactly which option suits your garden and lifestyle best.
Quick Verdict
Cordless mowers win for small to medium gardens, low maintenance, and quiet operation. Petrol mowers edge ahead for large properties and heavy-duty use, though they require more upkeep. For most UK gardeners, a modern cordless mower offers the best balance of convenience and performance.
Cordless Lawnmowers Explained
Cordless electric mowers have revolutionised garden maintenance over the past decade. These battery-powered machines use rechargeable lithium-ion batteries—typically 18V to 58V—to drive their cutting deck, eliminating the need for petrol and oil. Leading brands like Ego, Makita, and DeWalt have perfected the technology, delivering impressive cutting power in a lightweight package.
The cordless market offers models to suit every garden size. A mid-range 40V cordless mower (around £300–£500) will comfortably handle most suburban lawns, while premium models with larger decks and extended runtime push towards £700 and beyond. Battery capacity is measured in amp-hours (Ah), and most quality models include at least one battery. Some brands use interchangeable battery systems across their entire tool range, which is particularly useful if you already own other cordless garden tools.
Runtime is the key consideration. A typical 40V cordless mower with a 5Ah battery delivers 30–45 minutes of cutting time—more than enough for lawns up to 1,000 square metres. Larger properties may require a second battery or a dual-battery system to finish the job. Most brands offer fast chargers that can replenish a battery in 30–60 minutes, making it practical to swap and continue.
Petrol Lawnmowers Explained
Petrol mowers remain the workhorse of garden maintenance, particularly for larger properties and commercial use. These machines rely on small four-stroke (or occasionally two-stroke) engines, typically ranging from 100cc to 190cc, delivering consistent power throughout an unlimited runtime. You simply fill the tank with unleaded petrol and get cutting—no batteries to charge or worry about.
Quality petrol mowers from brands like Honda, Hayter, and Briggs & Stratton are built to last decades with proper care. Prices start around £250–£400 for basic models but can easily reach £800–£1,200 for robust machines with electric start and superior build quality. A mid-range 140cc model (roughly £450–£650) offers excellent value and enough power for most UK gardens, including larger properties.
Petrol mowers deliver consistent performance regardless of battery depletion because they run on fuel alone. They’re also typically heavier and more robust than cordless equivalents, designed to handle thicker grass, rougher terrain, and extended use. However, this power comes at a cost: they’re noisier, require regular maintenance, produce emissions, and need proper storage. If you have a large, demanding garden, a petrol mower’s unlimited runtime and raw cutting power can be invaluable.
Head-to-Head Comparison
Power & Performance
Both cordless and petrol mowers deliver sufficient cutting power for UK gardens, but they excel in different situations. Modern cordless models with brushless motors provide smooth, consistent cutting and handle regular lawn maintenance beautifully. The Ego LM2000 (around £450) and Makita DLM432Z (approximately £350) are excellent examples of machines that cut grass cleanly without bogging down.
Petrol mowers, however, have a genuine edge when tackling tough grass, thick weeds, or uneven terrain. Their engines maintain constant power delivery, never slowing as a battery drains. For large, demanding gardens or infrequent but heavy-duty cutting, petrol’s raw power is hard to beat. A Honda HRD536 (around £500–£600) will power through challenging conditions where a cordless mower might labour.
Ease of Use
Cordless mowers win decisively on ease of use. There’s no engine to start, prime, or adjust. Simply charge the battery overnight, press a button, and begin cutting. No mixing fuel, no checking spark plugs, no seasonal maintenance rituals. This makes cordless mowers ideal for occasional gardeners or anyone who values simplicity.
Petrol mowers require more initial effort: priming the engine, using the pull cord or electric starter, and warming up before cutting. Cold starts can be frustrating, particularly in winter. Switching off requires proper shutdown procedure. For regular gardeners willing to develop a routine, these tasks become second nature; for casual users, it’s an unnecessary hassle.
Maintenance
Cordless mowers require minimal maintenance. You’ll occasionally clean the cutting deck, perhaps sharpen or replace the blade annually, and charge the battery regularly. That’s genuinely it. The battery will eventually degrade—typically after 5–8 years—but most manufacturers offer affordable replacements (£80–£150).
Petrol mowers demand more attention. You’ll need to change the oil (usually every 50–100 hours), replace spark plugs, clean or replace air filters, and maintain the fuel system. Pre-season servicing is recommended, and you must properly winterise the machine if not using it during cold months. For hands-on gardeners, this maintenance is manageable; for others, it’s a significant commitment.
Noise & Emissions
Cordless mowers are substantially quieter—typically 70–75 decibels compared to a petrol mower’s 85–90 decibels. You can mow early morning or evening without disturbing neighbours. They produce zero emissions, beneficial for both air quality and your own health. This is particularly valuable for smaller UK gardens where noise travels easily between properties.
Petrol mowers are noticeably louder and emit greenhouse gases and pollutants. Many areas now have noise restrictions during certain hours, which petrol mowers may breach. For environmentally conscious gardeners, this is a significant drawback. However, the noise isn’t a dealbreaker for those with larger, more isolated gardens.
Running Costs
Cordless mowers have minimal ongoing costs. Electricity to charge a battery costs mere pence per session—typically less than 5p. Over a season, you’ll spend perhaps £5–£10 on electricity. Blade replacement is infrequent and inexpensive. Battery replacement eventually costs £80–£150, but spreads across 5–8 years.
Petrol mowers require regular fuel purchases, typically £15–£25 per season for an average garden. Oil changes, spark plugs, and air filters add another £20–£40 annually. Servicing by professionals costs £40–£80. Over a decade, the cumulative running costs are noticeably higher than cordless alternatives.
Garden Size Suitability
Cordless mowers suit gardens up to 1,500 square metres comfortably with a single battery. Larger properties may need dual batteries or accepting that you’ll charge mid-session. They’re perfect for suburban UK gardens—the most common size. If you have less than 1,000 square metres, a cordless mower is genuinely the better option.
Petrol mowers shine on larger properties exceeding 1,500 square metres, or on rough, demanding terrain. With unlimited fuel (a jerry can keeps you going indefinitely), they’re ideal for acreage. They’re also better for occasional heavy-duty cutting where you need maximum power without battery constraints.
Comparison Table
| Feature | Cordless Electric | Petrol |
| Typical Price | £300–£700 | £250–£800 |
| Battery/Fuel | Rechargeable lithium-ion | Unleaded petrol |
| Runtime | 30–60 mins per battery | Unlimited (fuel dependent) |
| Cutting Width | 32–43 cm | 38–51 cm |
| Suitable Garden Size | Up to 1,500 m² | 800 m²+ (unlimited) |
| Noise Level | 70–75 dB | 85–90 dB |
| Emissions | Zero | Petrol/CO₂ |
| Starting | Press button | Pull cord or electric starter |
| Maintenance | Minimal (clean deck, sharpen blade) | Oil changes, spark plugs, servicing |
| Running Costs | £5–£10 per season | £35–£60 per season |
| Interchangeable Batteries | Often compatible with tool ranges | N/A |
| Best For | Small–medium gardens, convenience | Large gardens, heavy-duty use |
Who Should Buy Cordless?
Cordless mowers are ideal if you have a suburban UK garden (under 1,500 square metres), value convenience and quiet operation, and want minimal maintenance. They’re perfect for people who mow regularly—weekly or fortnightly—because the workflow is straightforward: charge overnight, cut, store. You’ll benefit from the peace of mind knowing there’s no engine to maintain or fuel to worry about.
If you already own cordless tools from brands like DeWalt, Makita, or Ego, a cordless mower makes even more sense. You can share batteries across your entire toolkit, reducing the total investment. Environmentally conscious gardeners will appreciate zero emissions and the ability to mow early morning or late evening without disturbing neighbours.
Cordless mowers are also excellent for older gardeners or anyone with mobility concerns. The lighter weight (typically 20–28 kg) makes them easier to manoeuvre, and the simple electric start eliminates the physical strain of pull-cord starting.
Who Should Buy Petrol?
Petrol mowers suit you if you have a large garden (1,500+ square metres), infrequent cutting (seasonal rather than regular), or demanding terrain with rough grass and obstacles. They’re ideal if you prefer raw cutting power and aren’t bothered by noise or emissions. Many experienced gardeners prefer petrol mowers simply because they enjoy the mechanical simplicity and proven reliability.
If you already have a petrol mower that works perfectly, there’s no compelling reason to replace it. Petrol machines are durable—many models last 15–20 years with reasonable care. They’re also easier to repair independently; parts are inexpensive and widely available, and almost any competent mechanic can service them.
Consider petrol if you value the occasional heavy-duty cutting session more than regular, light maintenance. Some gardeners also prefer the feel of using a proven, established technology rather than newer battery systems.
Frequently Asked Questions
How long do cordless mower batteries last?
Most quality lithium-ion batteries retain 80% capacity after 5 years and typically last 7–10 years before noticeably degrading. When replacement becomes necessary, expect to pay £80–£150 depending on capacity and brand. Many manufacturers offer extended warranties on batteries, typically 3–5 years, which provides extra security.
Can I use a cordless mower in wet grass?
Most cordless mower manufacturers advise against cutting soaking wet grass, as moisture can damage the motor and battery contacts. However, light dew or rain is fine—the electrics are properly sealed. Petrol mowers handle wet grass without issue, but the cut quality suffers and grass clumps easily. For best results, wait until grass dries slightly after rain, regardless of mower type.
Are petrol mowers really better for large gardens?
For gardens over 2,000 square metres, yes—unlimited runtime is genuinely valuable. However, many people overestimate their garden size. Most suburban UK plots are 400–1,200 square metres, where cordless mowers with dual batteries are perfectly adequate. Measure your garden before deciding that petrol is necessary.
What’s the typical lifespan of each type?
Cordless mowers realistically last 8–12 years before battery degradation makes them less practical (though the motor itself lasts much longer). Petrol mowers, with proper maintenance, often reach 15–20 years or more. This longevity is petrol’s strongest durability argument, though parts and repairs eventually add up.
Final Verdict
For most UK gardeners, a modern cordless mower represents the smarter choice: quieter, cleaner, easier to use, and cheaper to run. However, if you maintain a large property, enjoy mechanical work, or want proven long-term durability, a quality petrol mower remains excellent value. Consider your garden size, how often you cut, and whether convenience or raw power matters most to you—and you’ll make the right decision.