Cost Estimators vs. Quantity Surveyors Key Differences

Jun 14, 2024

Cost Estimators vs. Quantity Surveyors Key Differences

You may have come across various construction estimating services claiming to be the best way to win tenders and quote clients. Within the construction industry, two key estimating professionals are often confused with each other: Cost Estimators and quantity surveyors. While both are valuable to construction projects, they have distinct roles. In this blog, Cost Logic explores the differences between estimators and quantity surveyors and helps you determine which one is the best fit for your project.


A cost estimator is an essential part of the construction planning process. They provide initial cost estimations that help builders and subcontractors win tenders. Estimators must have a strong understanding of construction technologies, as their role involves interpreting blueprints, applying them to the site, and considering environmental factors. Ultimately, cost estimators help ensure projects are delivered on time and within budget.


A quantity surveyor is a qualified professional who advises and monitors construction costs before and during a project. After the construction period, they may also assist with tax depreciation schedules and replacement cost estimation (primarily for insurance purposes). Quantity surveyors need a tertiary degree and relevant work experience to be eligible for membership at the Australian Institute of Quantity Surveyors (AIQS), which ensures compliance with industry standards and regulations.


Estimators and quantity surveyors share a key similarity: they both help projects run smoothly. They craft reliable, accurate estimates that reduce financial risks and provide greater cost control to project managers. This ultimately helps builders achieve their project visions within a designated schedule and budget. Therefore, both cost estimators and quantity surveyors are crucial to a project’s success.


The key differences between estimators and quantity surveyors include:

  • The Projects They Take On: Quantity surveyors frequently manage larger and more complex projects, leveraging their AIQS accreditation and extensive skill set. They engage extensively in both public and private sector projects. In contrast, estimators typically focus on residential and smaller commercial projects.
  • The Priorities They Have: The primary focus of a cost estimator is to provide accurate and timely cost estimations to help clients win tenders. Quantity surveyors, on the other hand, prioritize providing the Bill of Quantities (BOQ), which details the materials and labor required to complete the project. The BOQ helps resolve potential discrepancies between tender documents and prepares a fair calculation of construction costs.
  • The Role They Play: Quantity surveyors support construction projects before, during, and after completion. Estimators, on the other hand, primarily work before a project begins, during the tendering phase. In this phase, they create a cost summary presentation based on labor, material, and feasibility requirements. After winning the tender and starting the project, professional estimators at Cost Logic provide ongoing support as new circumstances require updated cost estimates.

Need a cost estimator? The team at Cost Logic delivers fast and accurate solutions for your project. We collaborate with construction professionals across commercial and residential sectors, including builders, subcontractors, and renovators. We manage projects Australia-wide, especially for inner-city clients in Sydney, Melbourne, Brisbane, Perth. Our construction estimating services help you win tenders and successfully manage your projects. Our key services include:

  • Section 94 estimates
  • Cash flow projections
  • Preparation of tenders

Additionally, our sister company, Section94, can assist with various quantity surveying needs, including bank prefunding, construction budgets, and progress claims.

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