Contracting authorities must award public contracts based on the most economically advantageous tender assessed from the point of view of the contracting authority. That tender shall be identified on the basis of the price or cost, using a cost-effectiveness approach and may include the best price-quality ratio, which shall be assessed on the basis of criteria linked to the subject-matter of the contract in question.
Award criteria shall ensure the possibility of effective competition and be accompanied by specifications that allow the information supplied by the tenderers to be verified to assess how well the tenders meet the award criteria. The contracting authority must also specify the relative weighting given to each of the criteria in the procurement documents, unless this is identified on the basis of price alone.
In accordance with the EU position, the UK Regulations require contracting authorities to ask the tenderers to explain the price or costs proposed in the tender where tenders appear to be abnormally low in relation to the works, supplies or services.