Small Mercury Outboard Motors: The Full 2.5 to 30 HP Line-Up on One Page
Eleven FourStroke models, one family look, and a clear step between each. Find the one that suits your hull without clicking through eleven product pages.
Small Mercury outboard motors are Mercury Marine’s portable FourStroke petrol outboards from 2.5 to 30 HP, covering everything from inflatable tenders up to loaded 4.5 metre (15 ft) runabouts.
Aroha, the sailing club and the black cowls
Aroha ran the rescue boats at her sailing club, and every winter the committee asked the same thing: which motors do we replace this year? The fleet was a mix of whatever had been donated over a decade, five brands, three fuel types and a shelf of spare parts that fitted nothing.
Her pitch was simple. Pick one family and stick with it. She chose small Mercury outboard motors because the range stepped neatly from 2.5 HP up to 30 HP, which meant the club’s inflatable mark-laying tender and its 4.3 metre (14 ft) aluminium chase boat could run the same brand, share a service schedule and come from the same parts counter.
The tender got a 3.5 HP that the juniors could lift. The chase boat got a 20 HP EFI that started first pull on frosty mornings. The spare parts shelf shrank to one box.
By spring the committee had stopped asking. One family, the right size at each end, and far fewer surprises on race day.
Which small Mercury outboard fits my boat?
Pick by hull size and load first. The line-up falls into four natural groups, each sharing weight and feel.
| Model | Best boat | Key features | From (USD) |
|---|---|---|---|
| 2.5 HP | Inflatables, tenders | One-hand carry, integral tank | $1,150 |
| 3.5 HP | Tenders, small dinghies | Same light frame, more push | $1,270 |
| 4 HP | 2.7–3.1 m (9–10 ft) dinghies | Forward, neutral, reverse gears | $1,620 |
| 5 HP | Dinghies, sailboat auxiliary | Same size as the 4, more power | $1,760 |
| 6 HP | Small tinnies, trolling | Top of the light group | $1,910 |
| 8 HP EFI | 3.5 m (12 ft) alloy boats | Fuel injection, easy starts | $2,580 |
| 9.9 HP EFI | 3.7–4 m (12–13 ft) alloy boats | Popular for HP-limited waters | $2,850 |
| 15 HP EFI | Planing 4 m (13 ft) hulls | Light for its power | $3,500 |
| 20 HP EFI | 4–4.3 m (13–14 ft) boats | Same size as the 15, more punch | $4,150 |
| 25 HP EFI | 4.3–4.5 m (14–15 ft) boats | Smooth multi-cylinder feel | $5,200 |
| 30 HP EFI | Loaded runabouts | Top of the small range | $5,800 |
Should I choose a carburetted or EFI small Mercury?
Choose EFI if you want easier starting and fewer fuel headaches; choose the smaller carburetted models if carry weight and price matter most.
From 8 HP upward, the Mercury range uses electronic fuel injection, which meters fuel precisely, starts well in the cold and copes better with a motor that sits between trips. The 2.5 to 6 HP models keep things simple with a carburettor, which is why they stay light and affordable. Either way, run fresh petrol and a stabiliser if the motor will sit for weeks.
Top small Mercury outboard motors by use
Our quick picks from the full range. Prices are starting prices in USD.
How do I pick the right small Mercury in 4 steps?
- Check the capacity plate for maximum HP and weight.
- Measure the transom: about 38 cm (15 in) for short shaft, 51 cm (20 in) for long shaft.
- Pick the group from the table, then the top model your plate and budget allow.
- Add the extras: a marine battery for electric start, a spare prop and a flush kit.
Small Mercury outboard motors: FAQ
What is the smallest Mercury outboard?
The Mercury 2.5 HP FourStroke is the smallest petrol model in our range, from $1,150. It is built for inflatables and tenders and carries in one hand.
Are small Mercury outboards 2-stroke or 4-stroke?
Every small Mercury we sell is a FourStroke. They run on straight unleaded petrol with oil kept in a separate sump.
Which small Mercury outboard is best for a tinnie?
For a 3.5 to 4 metre aluminium boat, the 9.9 HP EFI is the usual pick. For a 4 to 4.3 metre boat you want to plane with two aboard, look at the 15 or 20 HP EFI.
How often should a small Mercury outboard be serviced?
Follow the owner’s manual. Typically there is a first check after the break-in period, then a service every 100 hours or once a year, whichever comes first.
Eleven Mercurys. One is built for your boat.
Send us your hull length and capacity plate and we will name the model.