It is October, and your CFO wants next year's budget by the end of the month. You have twelve departments waiting on guidance, a board meeting in three weeks, and hiring plans that need approvals yesterday.
So you do what everyone does: open last year's budget, add 5% across the board for inflation, bump engineering by 20% for the new product initiative, and call it done. Two weeks of work instead of two months. Everyone's happy.
Then April rolls around. You're staring at a variance report that shows Marketing is 30% over budget, but they swear they didn't change anything. Turns out you've been carrying a $180K one-time rebrand project in their baseline for three years running. Every year you added 5% on top of it. That one-time expense has compounded into $203K of permanent budget that nobody actually needs, but everyone assumes is critical because "it's always been there."
Meanwhile, sales sits 40% under budget despite closing a record quarter. Why? Last year they had eighteen account executives. This year they have twelve after you automated lead qualification and shifted to inside sales. But your incremental budgeting process assumed the old model, so you forecasted for a sales motion that no longer exists.
This represents the double-edged promise of your incremental budgeting process. It works fast, but speed can hide problems. When you build on last year's foundation, you inherit everything. You get the good, the bad, and the $180K mistake nobody questioned because rolling it forward felt easier.
Incremental budgeting helps you build next year's new budget by picking up where you left off. Instead of building a new budget from scratch, you start with your previous budget and make the tweaks you know are coming. Most companies use it because it feels legitimately fast, familiar, and skips forcing you to rejustify every dollar you spent. If you navigate tight deadlines and manage multiple departments, an incremental budget keeps things moving without forcing you to rebuild everything every cycle.
But speed has trade-offs that show up later. When you lean on last year's budget, you can accidentally carry over old problems or miss major shifts in your business model. The trick is knowing when incremental budgeting works, how to adjust it properly, and when you need to stop and do a deeper review instead.
Definition of incremental budgeting
Incremental budgeting means you use your previous budget as your starting point and then adjust for what comes next. Instead of justifying every expense from scratch (that's zero-based budgeting), you zoom in on what changes, like inflation, new hires, or a new project.
The core formula is simple:
Your new budget = previous budget + incremental adjustments + new expenses
You can make those adjustments a flat percentage, tweak specific line items, or tie them to business drivers like headcount or revenue. However you do it, you simply layer on top of what you already have.
This approach really shines in collaborative planning environments. Departments submit budgets fast, and finance teams pull them together without fuss.
Pros and cons of incremental budgeting
Evaluating the pros and cons of incremental budgeting helps you decide if this method fits your current business needs. Here is a quick breakdown to help you weigh your options and find the right balance.
Pros:
- Saves significant time and administrative effort during budget season.
- Provides predictable funding for departments with consistent operations.
- Simplifies variance tracking since you build directly off previous numbers.
- Relieves your finance team from rebuilding the entire budget from scratch.
Cons:
- Carries forward past inefficiencies and wasteful spending automatically.
- Ignores strategic shifts or major structural changes in your business model.
- Fails to separate routine inflation from genuine, value-adding growth.
- Compounds historical mistakes if you leave one-time line items in your baseline.
Incremental budgeting vs. zero-based budgeting
When you compare incremental budgeting with zero-based budgeting, you encounter two entirely different planning philosophies. Incremental budgeting assumes your previous budget is mostly accurate and only requires minor adjustments. Zero-based budgeting assumes nothing. Under a zero-based approach, you start at zero and must justify every single dollar you plan to spend, regardless of last year's numbers.
Incremental budgeting wins on speed and administrative ease. It perfectly suits stable departments with predictable costs, like facilities or standard operational overhead. Zero-based budgeting delivers rigorous cost control. It works best for companies experiencing structural changes, or for highly variable departments like marketing where programs change drastically year over year. Use incremental budgeting to maintain steady operations, and choose zero-based budgeting when you need to eliminate bloat or realign spending with a completely new strategy.
The benefits of incremental budgeting
- Incremental budgeting solves the problem of budgeting taking forever. Most teams spend 2-4 weeks on incremental budgets rather than the months required for zero-based budgeting. You spend less time in spreadsheet minutiae and more time on strategic decisions that actually move the business forward.
- This approach delivers predictable funding for stable operations. Department heads expect consistent funding with sensible updates when operations remain stable. That clarity reduces anxiety during budget season and helps with long-term planning. People can make hiring and investment decisions without worrying that finance will slash their budget by 40% because someone decided everything needs re-justification.
- Catching meaningful variances feels easier. Since you build off previous data, it makes catching discrepancies simple. If you budgeted $100K for marketing and planned for a 10% bump but only see 5%, you know exactly where to look.
- Incremental budgeting dramatically reduces administrative burden for stretched finance teams. You skip asking every team to justify every dollar. You ask what changes and why. This keeps your conversations focused and productive.
Incremental budgeting methods: 5 approaches
Incremental budgeting rarely follows a one-size-fits-all model. Different teams use different tweaks based on how their business works and how much detail they want. Review each line item before rolling it forward to decide which method best suits your goals.
Standard flat percentage approach
This approach keeps things straightforward. You might apply a flat 3% increase to this year's budget to account for inflation, or pull all line items back by 5% to cut costs. It works fast, but it treats every expense exactly the same.
Line-item incremental method
Under this method, you tune individual lines with specific assumptions. Adjusting line items individually gives you more control over your incremental budget. Maybe facilities jumps 2% for rent, subscriptions jump 8% from extra users, and salaries get adjusted for merit raises and new hires. It takes more work, but delivers way more accuracy.
Inflation-adjusted incremental approach
Here you adjust specifically for market trends. Apply 3.9% to salaries from benchmarking data or 3.2% to utilities using CPI forecasts. Every category gets its own rate based entirely on real market signals.
Driver-based incremental method
This approach links spending to metrics that drive your business. Support scales directly with your customer count. Cloud costs follow your revenue. Recruiting adjusts with your headcount plans. Your budget tracks exactly with your true business growth.
Hybrid incremental zero-based approach
Many finance teams keep the incremental method for stable, recurring costs like rent or insurance. They then switch to zero-based justification for variable items like marketing campaigns or professional services. You get maximum efficiency plus deep control where it matters most.
Choose your approach based on your growth rate, how much change you manage, and how precise you need your numbers to be. If things hold steady, a simple method works beautifully. If you experience rapid growth or launch new business lines, you will want something more sophisticated.
Key components and considerations
To execute incremental budgeting effectively, pay attention to these critical elements:
Selecting the right base period
Your choice of baseline materially affects accuracy. Prior year actuals provide a clean and objective base, but they potentially feel outdated if your business evolved. The current year forecast stays up to date but might carry forward temporary changes you prefer not to perpetuate. An approved previous budget offers a reliable starting point, but it may not reflect the reality of what actually happened.
Defining adjustment factors
Set explicit rules for every increment so department heads understand your exact methodology. Decide if you are adjusting for inflation and clarify which index you use. Define the growth targets that matter most, whether that means revenue, headcount, or customer count. Document your assumptions clearly so team leads understand why their budget increased 8% while another department received 3%. Transparency prevents resentment and builds financial trust.
Handling one-time expenses
Watch out for project costs sneaking into next year's baseline. If you moved offices for $50K last year, do not let that become your new normal. Pull out one-off expenditures completely before adding your new increments.
Step-function costs
Some expenses jump in distinct steps. One new teammate does not change the rent. Twenty new teammates might mean signing a new building lease. The same logic applies to software. You could pay the same flat rate until you hit a user threshold, and then pay significantly more. Do not assume all costs grow smoothly.
Contractual changes and renewals
Build known cost jumps directly into your base. If your insurance costs go up 12% next year, plug that number in directly rather than relying on a blended percentage.
Growth and transformation challenges
If your company grows fast or shifts strategies, your old numbers might steer you wrong. Use incremental budgeting strictly for what stays stable, but plan your changing areas in sharp detail.
Benchmarks and rules of thumb
Common patterns emerge when teams implement incremental budgeting successfully:
- Most stable companies use 2-5% increases for basic cost growth or general inflation.
- High-growth companies often ramp up by 15-30% when budgets need to scale with sales or hiring goals.
- Budget cycles usually finish 40-60% faster when powered by an incremental budgeting process.
- Incremental methods work best on predictable costs like rent, salaries, and utilities, which usually account for 60-80% of spending.
- The leftover 20-40% gets a much closer look through detailed reviews.
- Firms often set aside 5-10% of the total budget for contingencies or strategic reserves.
- Quarterly reforecasting keeps your budget accurate and completely up to date.
These patterns help you gauge if your team’s on track or needs to dial in your process.
Common pitfalls
Incremental budgeting sometimes leads to issues. Here is how to navigate them successfully and build a stronger plan.
Perpetuating inefficient spending
The biggest risk involves carrying forward costs that you no longer need. If you spent $200K on a project last year and just add 3%, your incremental budget is based on history, not need. Always verify that your increments tie back to current operations.
Ignoring structural changes
If your business model shifts, like moving from field sales to inside sales, last year's spending metrics probably miss the mark. Reset your baseline entirely when your core strategy changes. If you successfully automate a manual process, adjust your headcount budget to reflect those real savings.
Uniform increments across departments
Adjusting every team by the same percentage ignores real priorities. Sometimes engineering needs a 25% boost for new products, but finance only needs 3% for inflation. Adjusting line items individually gives you more control and aligns your spending with business reality, rather than just corporate routines.
Not separating inflation from growth
If you increase budgets by 5%, but inflation consumes 3% of that jump, you only gain 2% in real growth. Break out your inflation funds separately from your new investment funds to get a clear picture of your purchasing power.
Leaving one-time expenses in the base
Big one-off expenses will skew your future budgets heavily if you leave them in. Clean up your baseline meticulously so you do not get stuck paying for last year's unusual surprises.
Compounding inefficiency
Even small inefficiencies multiply over time. If your baseline gets bloated early on, annual percentage increases just make the bloat larger. Run periodic zero-based reviews when you have the time to keep your operations incredibly lean.
Ignoring seasonality and timing
Timing always matters. If you spent your entire marketing budget in Q4 one year and Q1 the next, you will see a big year-over-year change that does not give you any real insight. Adjust carefully for business timing when you set your initial baseline.
How to set up your incremental budgeting process in Runway
Runway's planning platform takes incremental budgeting from an abstract idea to a concrete reality. Small, scrappy finance teams and independent model owners can build off real numbers, adjust figures transparently, and see exact changes over time. Here is how to set up your incremental budgeting process in Runway.
Step 1: Import historical actuals as your baseline
Start by importing actuals from your accounting system, ERP, or HRIS. Runway connects seamlessly to over 750 systems, including NetSuite, QuickBooks, and Salesforce. These real business numbers become your trusted base for all new adjustments.
Your data flows straight into tables in Runway, and forecast formulas create future values starting from your historical base. By default, these formulas copy last month's value or add a standard growth rate, so your model stays perpetually up to date.
Step 2: Set up your forecast formulas
Configure your formulas to match your true baseline spending. For steady costs, that means repeating last year's budget values. For varying expenses that track with specific business drivers, intelligently link them to headcount, revenue, or other key performance metrics. This baseline reflects your actual operational run rate before you layer on any prospective changes.
Step 3: Override specific periods with incremental adjustments
Use Runway to override forecast values neatly on top of your existing formulas. If you want to model a 4% merit increase, add a new hire, or update a specific vendor rate, just override the specific months and add a descriptive tag.
For example, say your cloud costs run flat at $50K a month and you expect a 10% hike in June. Simply override June to $55K for your product launch plan. The rest of the year remains untouched unless you explicitly change it.
Step 4: Use plans to track and categorize changes
Link your individual tweaks back to bigger strategic projects. Tag each override, and you can see exactly how much of your budget increase comes from merit raises, new hires, or revenue growth all in one convenient place. If multiple strategic plans hit the same budget line, tag them both. This elegant feature gives you full transparency on every single budget move.
Step 5: Spread adjustments across time periods
Stretch a specific plan smoothly across months to manage annual or multi-period spending. You can add a $120K annual expense once, and spread it cleanly at $10K per month, or weight it heavier toward your busy season. For percentage increases, you can apply your rate and let it easily repeat across subsequent months, or use dynamic rates as your business dictates.
Step 6: Create scenarios to compare increment options
Model vastly different assumptions using Runway Scenarios without breaking your core plan. Try a 3% increase across the board, or test different budget bumps by department to see how it impacts your incremental budget. Run a separate scenario with driver-based scaling. Compare all your options side by side and confidently pick what fits best. Each scenario stands completely alone. Once your stakeholders align on the path forward, merge your winning scenario.
Step 7: Set up continuous reforecasting
Incremental budgeting pairs perfectly with ongoing, proactive reforecasting. Sync your actuals safely from your ERP or accounting system every single month. Set reliable monthly or quarterly checkpoints where you track variance between your plan and your real world results. Adjust your business assumptions as you go, ensuring your budget happily keeps pace with your business reality.
Step 8: Document your increment logic
Use Runway's clean planning pages to explicitly capture your reasoning behind each decision. When you override a specific value, add a quick, helpful note on the business logic. These notes prove incredibly helpful during tense budget reviews and keep everyone on your financial team perfectly in sync.
The clear audit trail gives you instant insight. If an expected increase fails to deliver the expected operational outcome, you just check the plan history and immediately learn from it.
Move forward confidently
Incremental budgeting keeps your financial planning manageable when operations hold steady. It dramatically trims down your administrative work while still enabling you to track and analyze your spending in meaningful detail.
The secret involves applying your increments thoughtfully. Base your vital updates on your actual current needs, rather than just repeating what you did last year. Adjust intelligently by individual department and category. Separate your one-time historical costs precisely from your forward-looking recurring spend. Pair your incremental budget with regular, disciplined reforecasts so you stay delightfully sharp all year round.
Runway helps you securely build on real numbers, adjust everything with total transparency, and keep every single change beautifully organized. You get incredibly fast budgeting combined with total visibility and full financial control. Stop firefighting and start leading your company forward.
Want to streamline your budget process? Request a demo and see how quickly you can take control of incremental budgeting (and actually start to enjoy it).