Glossary

Provisional sum

A provisional sum is a budget placeholder in a quote for work not yet fully specified. It is included in the total until the scope is fixed and repriced.

Also called: provisional allowance, PS sum

Kitchens, landscaping and specialist trades are often provisional on early quotes. The number is not a fixed price: it is permission to spend up to that cap when the detail is chosen.

When you compare two builder quotes, note which items are provisional on each file. A lower total with more provisional lines may rise once specifications are agreed.

Before you pick a builder, align provisional items on the tender checklist: same scope, same allowance, same trigger for a final price.

What this means for you

Treat every provisional line as a question. Ask what fixes the price and what happens if the allowance is exceeded.