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Build next year's department budget from last year's costs
Get a first-draft budget based on last year's spending, known changes and inflation assumptions, with every line explained.
When to use it
During annual budget planning
Step by step
Export last year's actuals
Export 12 months of costs by line for your department, plus this year's budget if you have it.
List the known changes
Note planned hires, leavers, contracts ending or starting, projects and any price rises you've been told about.
Draft the budget
Attach the export and paste this prompt.
Prompt to copyHere are last year's monthly costs for [department] and our known changes for next year: [list]. Build a draft budget for [year] as a table: Cost line | Last year actual | Next year budget | Change | Reason. Assume [x]% general price increase unless I've said otherwise. Spread each line across 12 months, noting any lines that are seasonal or one-off. Then list: lines that look unusually high or low last year, and three questions I should ask before finalising. Show your workings for any line over [£10,000].Challenge and adjust
Go through each line with budget holders, change anything that doesn't reflect reality, and check the totals in your own spreadsheet.
Get it approved
Submit the final version through your usual sign-off process, keeping the reasons column so anyone can see how each number was reached.
What you get
Software licences | £38,400 | £44,100 | +£5,700 | 5% price rise plus 4 new users from March. Temporary staff | £22,000 | £8,000 | -£14,000 | Last year covered a long vacancy, now filled. Question: will the office move in Q3 change the rates bill?
Tips
- Ask for a lean and a stretch version so you can show leadership the trade-offs.
- Salary details are sensitive; use grades or totals rather than named individuals.