Why is the lowest bid not the cheapest?

What levelling actually does

Bidders do not price identical things. One excludes builder’s work in connection. One leaves a rate blank and writes “included elsewhere”, and it turns out not to be included anywhere. One carries a provisional sum that another has priced properly. One has read the quantities differently.

Levelling normalises all of that to a common scope before anyone compares a total. It is unglamorous, it is where the evaluation is genuinely won or lost, and it is the step that gets compressed when the award date is close.

The chain that follows from skipping it

Award to the lowest incomplete bid. The missing scope surfaces the moment work starts, because it was always going to. It becomes a variation, priced without competitive tension, by the one contractor who is now on site.

The “saving” is gone within months, and what remains is a dispute about whether the exclusion was clear. It usually was clear — in the bid nobody read closely enough.

The rule

Compare levelled bids, not submitted bids. The raw lowest total tells you which contractor was most optimistic, or most aggressive, or most careless about reading the specification. It does not tell you which offer costs least.

And it cuts the other way too: the bid that looks expensive is sometimes the only one that priced the whole job.

Terms

• Bid Levelling
• Unbalanced Bid