The terms are often used interchangeably, but an estimator and a quantity surveyor do different jobs. The simplest way to think about it: an estimator focuses on winning the work at the right price, while a quantity surveyor focuses on controlling cost once the work is underway.
What an estimator does
An estimator prices construction work to produce a competitive tender. They:
- read drawings and specifications,
- take off quantities,
- obtain supplier and subcontractor quotes,
- build up rates for labour, materials and plant,
- and assemble the bid.
Their job is largely front-loaded — before a contract is awarded.
What a quantity surveyor does
A quantity surveyor (QS) has a broader, longer role across the whole project lifecycle. They:
- prepare cost plans and bills of quantities,
- run tenders,
- value work in progress for interim payments,
- manage variations and change,
- handle contractual matters,
- and agree the final account.
A QS is involved from the earliest cost plan right through to the closing figure.
The overlap
Many estimators come from a QS background, and plenty of firms offer both services. On a smaller job the same person may estimate the work and then manage its cost. On a larger project the roles are usually separate — an estimating team wins the work, and a commercial/QS team manages it on site.
Which do you need?
- Need a price to start a project or compare quotes? You need estimating.
- Need someone to manage cost, payments and the final account across a build? You need a quantity surveyor.
Browse estimators and quantity surveyors by trade and location to find the right specialist.