Budget vs Forecast: What's the Difference? (With a Multifamily Example)

On June 30, your variance report says a property is $31,800 behind on NOI. Your forecast says it will finish the year $130,400 behind. Both numbers are right, and the distance between them is the whole budget vs forecast question.

The short version: the budget is what you committed to. The forecast is where you now expect to land. You need both, and one should never overwrite the other.

Quick Answer A budget is the approved financial plan for a set period, usually a fiscal year. It stays fixed so performance can be measured against it. A forecast is your current estimate of where results will actually land, and it changes as new information comes in. The math is Full-Year Forecast = Actuals to Date + Forecast for the Remaining Months. The budget answers "what did we commit to?" The forecast answers "where are we headed?"

What Is a Budget?

A budget is a financial plan someone has approved. It sets income and spending targets for a fixed period, usually 12 months, and it becomes the baseline for every result that follows.

In multifamily, that's a property-level plan for income, operating expenses and net operating income (NOI), with capital projects planned separately. The owner or asset manager signs off after a long review. Vizibly's State of Multifamily Budgeting report puts a typical season at 111 days.

That calendar builds in a limitation: assumptions age. If a calendar-year budget kicks off in August, the assumptions behind next December's numbers are 16 months old when December arrives. Asset Living moved its budget workshops from August to October to work from more current-year actuals. That helps, and those December assumptions are still 14 months old.

None of this makes the budget wrong. You can't measure drift against a line that moves with you, so the baseline has to hold still. If you're building one now, start with our property management budget guide.

What Is a Forecast?

A forecast is your best current estimate of how the period will end. It combines what has already happened with what you now expect for the months left:

Full-Year Forecast = Actuals to Date + Forecast for the Remaining Months

Finance teams often name a forecast by that split. A 3+9 has three months of actuals and nine of forecast. A 6+6 has six of each. A 9+3 has nine and three. Each time a month closes, a real number replaces an estimate.

In multifamily, you'll usually hear this called a reforecast, and most operators use the two words interchangeably. In this article, "forecast" is the estimate and "reforecast" is the act of updating it.

A forecast has one job: to be accurate. Targets belong in the budget.

Conditions keep that job busy. NMHC's Market Tightness Index measures whether national apartment markets are tighter or looser than three months earlier, with 50 meaning unchanged. In 2026 it read 32 in January, 49 in April, 57 in July and 47 in October. On rent growth and vacancy, Freddie Mac's investor presentation, as of June 30, 2026, says "projections for 2026 have been revised downward." A budget approved last fall can't absorb any of that. A forecast can.

Budget vs Forecast: Key Differences

Corporate Finance Institute's comparison puts it neatly: "A budget sets targets, a forecast adapts to changes, and projections explore possibilities." In practice, the differences look like this:

A forecast vs budget gap isn't a failure on its own. A gap you find in June leaves six months to respond. The same gap in the year-end report leaves an explanation to write.

Which Comes First, the Budget or the Forecast?

They take turns. To build next year's budget, you start from a forecast of how this year will end: year-to-date actuals plus an estimate of the remaining months. Once approved, that budget becomes the baseline, and often the starting point, for the first forecast of the new year.

So a sloppy forecast costs you twice. It misleads you this year, and it hands next year's budget the wrong starting point.

Budget vs Forecast Example: A 200-Unit Property at Mid-Year

Here's the comparison on one illustrative property: 200 units at an average rent of $1,500. At that size, one point of occupancy is 2 units, or $3,000 a month.

The approved budget assumes 95% average occupancy, insurance at $20,000 a month and 80 turns at $2,500 each. It's June 30, and you're building a 6+6 forecast:

To keep the math readable, rental income here is just rent at the stated occupancy, with no loss to lease, concessions or bad debt. Total income is the line many statements call effective gross income (EGI).

Notice what didn't move: the budget is still $1,800,000 of NOI, the number the owner approved.

What the Variance Report Shows vs What the Forecast Shows

Through June, the budget called for $900,000 of NOI. So on the same day, the same property gives you two different answers:

The forecast sees about four times the gap, because three things are moving that the year-to-date column can't fully show yet.

Occupancy. The property ran 94% through June, one point under budget. That's $3,000 × 6 months = $18,000 short. Summer renewals are tracking below plan, so the forecast uses 93% from July, two points under: $6,000 × 6 months = $36,000. Rental income ends $54,000 under budget, and other income running $500 a month ahead gives back $6,000.

Insurance. On June 30 the variance is exactly $0. The policy renews July 1 at $26,000 a month, which adds $6,000 × 6 months = $36,000. Your budget-to-actual report won't show that until July closes. The forecast shows it the day the quote arrives. Renewals can move that far and further: in a small Minneapolis Fed survey of 35 multifamily owners in the Upper Midwest, premiums rose an average of 45% from 2023 to 2024.

Make-ready. Through June the property has done 48 turns at $2,600. The forecast adds 48 more at $2,700, for 96 turns at an average of $2,650. Split the variance into volume and rate:

Budget:   80 turns × $2,500 = $200,000
Forecast: 96 turns × $2,650 = $254,400

Volume variance = (96 − 80) × $2,500 = $40,000
Rate variance   = ($2,650 − $2,500) × 96 = $14,400
Total variance  = $40,000 + $14,400 = $54,400

Sixteen extra turns point to retention. An extra $150 a turn points to vendors or scope. They need different fixes.

Everything else stays at budget for July through December ($680,000), because nothing new has been learned about those lines. You don't have to reforecast every line. Update the ones where you know something you didn't know before.

Why the Owner Cares About the Gap

Owners and lenders look at NOI against debt payments. Assume $1,400,000 of annual debt service (illustrative) and run the debt service coverage ratio:

Budget:   $1,800,000 ÷ $1,400,000 = 1.29x
Forecast: $1,669,600 ÷ $1,400,000 = 1.19x

If the loan had a 1.25x test (tests and how they're measured vary, so check the loan documents), the year-to-date report wouldn't raise the question. The forecast raises it with six months left to act.

Those six months are worth real money. Getting July through December back from 93% to 94% adds $18,000 ($3,000 × 6). Each avoided turn saves about $2,700 in make-ready. You probably can't change the insurance renewal. You can still work the lease renewals.

Budget vs Forecast vs Actual: How to Read the Comparisons

Three numbers give you more than one comparison, and each answers a different question. CFI's guide to FP&A variances names three: budget-to-actual, forecast-to-actual and forecast-over-forecast. Add forecast vs budget, and that's four:

The two you'll use most are simple subtraction:

Budget Variance = Actual − Budget
Forecast Variance = Full-Year Forecast − Budget

Whether a variance is good or bad depends on the line. Income above budget is favorable. An expense above budget is unfavorable, which is why the +$54,400 on make-ready is bad news. Our guide to property management KPIs covers budget-to-actual variance alongside the other numbers owners ask about.

If your owner report stops at actual vs budget, it only says what has already happened. Adding the forecast column shows what you expect next and what you're doing about it.

Budget, Forecast, Projection, Pro Forma: Other Terms You'll Hear

These words get swapped in meetings, which is how two people can say "the plan" and mean different numbers.

Reforecast vs Rolling Forecast

A standard reforecast still ends on December 31, so your view shrinks as the year goes on. By the 9+3, you can only see three months ahead.

A rolling forecast keeps the window the same length. CFI's rolling forecast guide describes it as regularly updated, with a new period added as each one passes. At the end of June, a 12-month rolling forecast covers July through next June.

That longer view can help seed next year's budget. It doesn't replace the budget, because owners still need a fixed plan to approve.

Where the Pro Forma Fits

Multifamily adds a fourth number. If an owner bought the property on a pro forma, the asset manager may measure results against that model as well as the budget. A property can beat its budget and still trail its underwriting.

So when an owner asks whether you're on plan, ask which plan.

How Budgeting and Forecasting Work Together

Budgeting and forecasting aren't competing methods. They're a loop, and it runs in the same order every cycle.

1) Lock the Budget

Keep the approved version read-only. If the owner approves a formal revision, save it as a new version with the date and the reason, and keep the original.

2) Close the Month and Load Actuals

Replace that month's estimate with the real number. Clean coding matters here, because a miscoded invoice becomes a false variance and then a bad assumption in the forecast.

3) Update the Drivers That Moved

Start with what you've learned: expirations, renewal rate, downtime, turn count, cost per turn, insurance quotes and tax notices. Renewal intent usually shows up about 60 days out, so it can change the forecast long before it reaches the P&L. Hold everything else at budget.

4) Compare the Forecast to the Budget and Explain the Gap

Write it in a sentence an owner can follow. From the example:

"We forecast NOI $130,400 under budget: $48,000 from lower income, mostly occupancy; $54,400 from make-ready, on 16 more turns at $150 more per turn; and $36,000 from the July insurance renewal. Other expenses are $8,000 under, which offsets part of that."

5) Decide What You'll Do About It

Give every meaningful gap an action, an owner and a date. Some gaps you accept, like an insurance renewal that's already bound. Others you can still work, like retention and turn scope.

6) Tell the Owner Before the Variance Report Does

A miss an owner hears about in July, with a cause and a plan, lands differently than one they discover in the year-end statement. That difference is most of the operator–owner trust gap.

How Often Should You Reforecast?

Quarterly is the floor, and monthly suits most operators because it follows the close. Some go further: the case for weekly reforecasting rests on the fact that variance reports often run on 45-day-old actuals, while renewal decisions are visible much sooner.

Whatever the cadence, aim for what the budgeting maturity model describes at Level 5: "Reforecasting is structured, not ad hoc."

This loop is also where spreadsheets start to creak. Every cycle means a fresh export, a new file and a reconciliation before anyone can think about the property. Vizibly pulls actuals from Yardi, RealPage or Entrata and rolls budgets, forecasts and actuals up across the portfolio, so the comparison starts from current numbers. If you're evaluating tools, here's how to choose forecasting software.

Common Budget vs Forecast Mistakes

• Overwriting the budget with the forecast. Once the baseline moves, the variances disappear, and so does the owner's reason to trust the report.
• Calling actuals plus remaining budget a forecast. That assumes every problem ends the day the month closes. In the example, the shortcut shows $1,768,200 of NOI ($868,200 + $900,000) and misses $98,600 of the gap.
• Forecasting to the budget. A forecast that always lands on budget is a photocopy. Someone is managing the number instead of estimating it.
• Padding the forecast. Sandbagging so you can beat it later teaches owners to discount whatever you send next.
• Forecasting totals instead of drivers. "Make-ready up 27%" can't be checked or acted on. "16 more turns at $150 more per turn" can.
• Never scoring the forecast. Compare last quarter's forecast to what actually happened. That's how you learn which assumptions keep missing.

FAQ

What is the main difference between a budget and a forecast?

A budget is a fixed plan that sets targets for a period, while a forecast is an updated estimate of where results will actually land.

Is a budget a forecast?

No. A budget is a commitment you're measured against and a forecast is an estimate you keep updating, though the approved budget is often the starting point for the year's first forecast.

What is the difference between a forecast and actuals?

Actuals are results already recorded in your books, and a forecast is an estimate of results that haven't happened yet. When a month closes, its actuals replace its forecast.

Do the budget and forecast have to match?

No. They usually drift apart as conditions change, and that gap is the useful part, because it shows how far the property is tracking from plan while there's still time to respond.

How often should a forecast be updated?

At least quarterly, and monthly for most operators so it follows the close. Some operators reforecast weekly to stay ahead of renewals and leasing.

What does 6+6 mean in a forecast?

It means six months of actual results plus six months of forecast, which together give a full-year estimate.

The Punchline

The budget is what you committed to. Actuals are what happened. The forecast is what's coming. The gap between the forecast and the budget is your to-do list, and it's only useful while there's still time to work it.

Keep the budget fixed. Keep the forecast honest. Tell the owner early.

Want your team explaining these gaps with confidence? Financials 101 for Property Managers covers volume × rate and forecasting, and it includes a variance statement builder.

Sources

• National Multifamily Housing Council, "NMHC Quarterly Survey of Apartment Conditions (October 2026)" (October 22, 2026). https://www.nmhc.org/research-insight/quarterly-survey/2026/nmhc-quarterly-survey-of-apartment-conditions-october-2026/
• Freddie Mac Multifamily, "Multifamily Business and Securitization Program Overview: Investor Presentation" (as of June 30, 2026). https://mf.freddiemac.com/docs/mf_securitization_investor-presentation.pdf
• Christina Spicher and Libby Starling, Federal Reserve Bank of Minneapolis, "Rising property insurance costs stress multifamily housing" (March 4, 2025). https://www.minneapolisfed.org/article/2025/rising-property-insurance-costs-stress-multifamily-housing
• Corporate Finance Institute, "Budget vs. Forecast vs. Projection: What Are the Differences?" (March 6, 2025). https://corporatefinanceinstitute.com/resources/fpa/budget-vs-forecast-vs-projection/
• Corporate Finance Institute, "3 Types of Variances Every FP&A Pro Should Know" (April 17, 2025). https://corporatefinanceinstitute.com/resources/fpa/types-of-variances-fpa/
• Corporate Finance Institute, "Rolling Forecast" (October 2, 2019). https://corporatefinanceinstitute.com/resources/accounting/rolling-forecast/