The Roomba Max 775 Combo is the more useful choice if you want a robot to mop hard floors as well as vacuum. The Max 715 Vac is the vacuum-only option. Do not buy the 715 expecting to add a water tank later and turn it into the 775: choose the cleaning job first.
UK price and stock change the decision
On 5 September 2026, iRobot UK listed the black 775 Combo with AutoWash dock at £599 and in stock. Its 715 Vac with AutoEmpty dock was £549 but unavailable. At those listed prices the gap is £50, so the 775 deserves consideration for mixed-floor homes. These are dated manufacturer prices, not guaranteed future offers.
The exact Amazon UK pages for Roomba Max 775 and Roomba Max 715 were both unavailable at our check. They are stock-check links. The iRobot links above are direct, non-affiliate alternatives; compare availability there before waiting for Amazon.
What you get with each model
| Feature | Max 775 Combo | Max 715 Vac |
|---|---|---|
| Floor care | Vacuum and roller mop | Vacuum only |
| Dock | Empties dust, washes and dries mop | Empties dust |
| Dock dimensions, L × W × H | 45.6 × 43 × 43.2 cm | 21.3 × 17.2 × 29 cm |
| Published suction | 30,000 Pa | 30,000 Pa |
These details come from the two iRobot UK product pages linked above. Equal advertised suction does not establish equal real-world pickup, and it is not a reason to buy the larger model if you will never use its mop.
Choose 775 for a real mopping job
Think about the kitchen and entrance areas you currently mop by hand. If they need regular attention, automation could be useful. The 775's roller system and dock add the relevant hardware. You still need room to access its tanks and a routine for checking and cleaning the equipment.
Measure the proposed dock location with tape, including space to open and service it. A dock that technically fits under a shelf may still be awkward to maintain. Check your floor manufacturer's guidance before using a robot's water or cleaning solution.
Choose 715 when vacuuming is the goal
For a home where carpet pickup is the main requirement and mopping is already handled, the smaller dock is a practical reason to consider the 715. Judge the actual offer when it is available. Do not pay an inflated marketplace price solely because its model number appears in a comparison.
Before you buy either
Check the exact 775 Combo or 715 Vac name, included dock, seller, warranty and return terms. Accessories and older Roombas often appear beside these models in search results. Start the first cleaning runs while you are home and check how the robot handles your rugs, thresholds and clutter.
This guide compares published product details and checked buying options. It does not assign a cleaning-test score or claim that either robot was tested in our home.
