The straight answer: an 8-wheel grab lorry load of inert muck (soil, clay, hardcore) typically runs £250–£420 per load in the South East, with London jobs at the top end. Mixed or contaminated waste costs substantially more because tip fees jump.
What changes the price
Material type — clean inert soil is cheapest; mixed construction waste adds £60–£120/load; hazardous or contaminated needs testing and specialist tips
Distance to tip — a grab lorry earns when it's tipping, not driving; jobs far from a licensed tip cost more
Access — the grab arm reaches ~3m over a fence or wall; awkward access means more time on site
Backloads — smart firms deliver aggregates (£40–50/tonne) on the return leg; if your firm offers both, ask for a combined price
Grab lorry vs skip — the honest maths
An 8-wheeler grab shifts roughly 16 tonnes (about 9m³) in one visit — the equivalent of two large skips — loads itself in ~20 minutes, and doesn't need a permit sitting on the road for a week. For anything over a couple of skips' worth, grab hire usually wins on cost per tonne.
Check the paperwork: whoever takes your muck must be a licensed waste carrier — ask for the licence number. Every reputable firm will show it without blinking.