Calculate the yardage
Excavation is volume work. Length times width times depth in feet, divided by 27, gives you cubic yards in the ground. Then apply the part beginners miss: soil swells when you dig it. A cubic yard in the ground becomes more than a cubic yard on the truck — the exact factor depends on the material, so learn the swell behavior of your local soils and build it into your hauling math.
Measure from the plans when they exist and from the site when they do not. For foundations, account for overdig and working room beyond the footing line. For trenches, length times width times depth per run, and do not forget the bedding and backfill volumes are different materials with different prices.
Judge the ground and the access
Two identical holes are different jobs when one is sand and the other is clay, caliche, or rock ledge. Ask what the neighborhood digs like, look at any exposed cuts nearby, and check soil information where it is available. You cannot see everything from the surface, which is exactly why the estimate needs assumption clauses — more on those below.
Access decides your equipment. A backyard pool dig with a three-foot gate is a different machine, a different production rate, and possibly hand work compared to an open lot. Note spoil pile room, overhead lines, septic systems, and anything the machine should not cross.
Price machine, operator, and hauling separately
Build the price from three blocks. Machine time: hours for your excavator or skid steer at a rate that covers ownership or rental, fuel, wear, and transport to the site. Operator labor: your loaded hourly cost. Hauling: loads times your per-load cost, or trucking hours, plus dump fees at the site you will actually use. How to price contractor jobs covers building blocks like these into a defensible total.
Mobilization is a real line on excavation work. Moving a machine to the site costs the same whether the dig is one day or five, so show it as its own line on small jobs or the small jobs quietly subsidize the big ones.
Locates and assumption clauses are not optional
Always have underground utilities located before digging — it is free in most places through the call-before-you-dig service, and it is the law in many. The estimate should state that locates are required before work starts and who is responsible for private lines like irrigation and invisible fence, which the public service does not mark.
Then write the two clauses that save excavation businesses: rock and water. State that the price assumes diggable soil, and that encountering rock, buried debris, or groundwater requiring dewatering changes the price by agreement before work continues. You are not being pessimistic; you are describing geology honestly.
What the customer should see
The estimate should show the scope in plain words (what gets dug, to what dimensions), the yardage, machine and labor basis, hauling and dump fees, backfill and compaction if included, site restoration that is or is not included, and the assumption clauses. 'Topsoil stripped and respread' versus 'rough grade only' is a difference customers care about at the end — write it at the start.
EstimateBook is handy here because excavation quotes collect details from the site walk: talk through dimensions, access, and assumptions by voice, review the drafted line items, and send a PDF from the truck. The draft is a starting point — verify every number against your own measurements before it goes out.