QUICK ANSWER
To create a business budget: start with your prior year revenue and expenses as a baseline, adjust for expected changes in the coming year, separate fixed costs (rent, insurance, software subscriptions) from variable costs (COGS, commissions, advertising), set revenue targets by month, and calculate the expected net profit at different revenue levels. Review your budget monthly against actual results and adjust forecasts for the remainder of the year when your actuals diverge significantly from your plan.
Key Takeaways
- A budget is a plan — a forecast is a prediction — your budget is your target for the year; as the year progresses, update your forecast to reflect what you now know will happen. Both are important: the budget holds you accountable; the forecast gives you an accurate current view of where the year will end.
- Fixed costs are your floor — variable costs scale with revenue — understanding which costs are fixed (paid regardless of revenue) versus variable (scale proportionally with sales) helps you model the break-even point where revenue exactly covers all costs.
- Most small businesses underestimate variable costs and overestimate gross margins — when building your budget, use conservative assumptions for revenue and gross margin; it’s better to over-deliver against a conservative budget than to miss an overly optimistic one.
- Review budget vs. actual monthly, not just at year-end — monthly budget review within 5 business days of month-end allows you to identify variances while there’s still time in the year to course-correct; year-end budget review is too late to act on most findings.
A business budget is the financial plan that connects your business goals to your daily operations. Without a budget, you’re running your business by looking in the rearview mirror — reacting to what happened rather than steering toward where you want to go. This step-by-step guide walks through creating a practical annual budget that you’ll actually use throughout the year.
Step-by-Step Business Budget Creation
Step 1: Gather Your Historical Financial Data
Before projecting forward, understand where you’ve been. Run a Profit and Loss report for the prior 12–24 months from your accounting software (QuickBooks Online, Xero, or Wave). Identify your actual revenue by month, your major expense categories and their actual amounts, your gross profit margin (revenue minus cost of goods sold), and your major fixed versus variable cost categories. This historical data is the foundation of your budget — projections that aren’t grounded in actuals are guesses, not plans.
Step 2: Set Revenue Projections
Project revenue month by month for the coming year. Consider: your historical growth rate and whether it’s sustainable; known contract renewals or cancellations; planned new product launches or service expansions; seasonal patterns in your business; and economic conditions specific to your industry. Create three scenarios — conservative (70% of hoped-for growth), base case (most likely outcome), and optimistic (strong growth) — and build your expense budget around the base case while stress-testing it against the conservative scenario to ensure your fixed costs are covered even in a weaker year.
Step 3: Project Cost of Goods Sold
COGS scales with revenue — if you project 20% more revenue, your COGS should increase proportionally (assuming consistent pricing and product mix). Express COGS as a percentage of revenue (your gross margin percentage) and apply that percentage to your monthly revenue projections. If you’re planning changes that will affect your gross margin — new suppliers, price increases, product mix shifts — adjust the percentage accordingly for the months those changes take effect.
Step 4: Project Fixed Operating Expenses
Fixed expenses don’t change with revenue — they’re paid every month regardless of sales volume. List each fixed expense category: rent, insurance premiums, loan payments, software subscriptions, salaries (for non-commissioned employees), utilities (base charge), and professional fees (accounting, legal retainers). Enter the expected monthly amount for each, accounting for known changes (rent increases, new software subscriptions, planned hires).
Step 5: Project Variable Operating Expenses
Variable expenses scale with business activity: sales commissions (percentage of revenue), marketing/advertising (often budgeted as a percentage of revenue), credit card processing fees (percentage of card volume), shipping and fulfillment costs, and contract labor (fluctuates with project volume). Express each variable expense as a percentage of revenue and apply it to your monthly revenue projections.
Step 6: Calculate Your Monthly and Annual Profit Projection
Projected Revenue − Projected COGS = Projected Gross Profit. Projected Gross Profit − Fixed Expenses − Variable Expenses = Projected Operating Income (before taxes). For each month and for the year total, this calculation shows whether your business is projected to be profitable at your planned revenue level. If the result is negative or uncomfortably thin, you’ve identified the problem while there’s still time to adjust — before the money is actually spent.
Tools for Building Your Business Budget
QuickBooks Online, Xero, and most accounting platforms include a budgeting feature that allows you to enter monthly budget amounts by account category, then run Budget vs. Actual reports that compare your plan to your real results in real time. Alternatively, Google Sheets or Microsoft Excel budget templates are widely available and allow more flexible modeling for scenario analysis. For businesses that want dedicated financial modeling tools, Fathom, Jirav, or Mosaic offer more sophisticated budgeting and forecasting capabilities connected to your accounting software.
Recommended Resources
Accounting All-in-One For Dummies — includes an extensive section on budget creation, variance analysis, and how to use your accounting software’s budgeting features to build a budget that connects to your monthly financial reports automatically.
QuickBooks Online for Beginners 2026 — covers how to set up a budget in QuickBooks Online’s budgeting tool, enter your annual plan, and run budget-versus-actual reports that show exactly where you’re over or under your plan each month.
Frequently Asked Questions
How often should I update my business budget?
Your annual budget should remain fixed as your plan for the year — changing the budget whenever actuals differ defeats the purpose of having a plan. Instead, maintain a rolling forecast separate from your budget: update the forecast monthly to reflect what you now know about the remainder of the year. By year-end, compare your actual results to the original budget (to evaluate how well you planned and executed) and to your most recent forecast (to evaluate how well your in-year forecasting improved). The budget measures plan quality; the forecast measures current reality.