A cash-flow calendar is a twelve-month table of the cash you expect to receive and pay out, with the balance at the end of each month. For an HVAC company it does one job above all others: it shows the seasonal low point, usually in spring or early fall, months before you hit it. This guide shows how to build a first version from your bank statements in an evening.
This is operating planning. It is not a lender forecast, a financial statement or tax advice, and we are not accountants. Your own CPA should prepare anything formal, and should give you tax instalment dates and amounts to include.
Why HVAC cash is so lumpy
Heating and cooling demand rises and falls with the weather, and so does cash. Payroll, truck leases, rent and software do not. The result is a pattern most owners feel without ever drawing:
- Late fall into winter: no-heat calls, furnace and boiler replacements, and strong collections.
- Late winter into spring: demand eases, invoices from the peak have been collected, and the bank balance starts to slide.
- Early summer: the first heat wave brings cooling calls and installs; cash recovers.
- Late summer into early fall: a second, smaller lull before heating season.
The exact timing varies by region. A heat-pump company on the BC coast has a flatter year than a furnace shop on the Prairies. The areas hub covers regional patterns.
Step 1: pull 24 months of bank history
From your business bank account, list for each of the last 24 months:
- Total deposits (cash in)
- Total withdrawals (cash out)
- Closing balance
Remove transfers between your own accounts, and loan advances, so you are looking at operating cash. Two years matter because one year can be distorted by a mild winter or a single large job.
Step 2: separate fixed and variable cash out
Go through one typical month and split withdrawals into:
- Fixed: wages and salaries, truck and equipment leases, rent, insurance, software subscriptions, loan payments.
- Variable: equipment and parts purchases, subcontractors, fuel, marketing spend that rises and falls.
Add up fixed costs and divide by about 4.3 to get weekly fixed cost. This becomes the unit for your cash floor.
Example: wages $61,000, leases $8,400, rent $4,200, insurance $2,100, software $1,300 and loan payments $3,000 make $80,000 a month in fixed costs, or about $18,600 a week.
Step 3: build the calendar
Use one row per month for the next twelve months. For each, project cash in and cash out from the same month in your history, adjusted for anything you know has changed: a new truck, an extra technician, a price increase.
| Month | Cash in | Cash out | Closing balance | Weeks of fixed cost |
|---|---|---|---|---|
| November | $298,000 | $236,000 | $182,000 | 9.8 |
| December | $312,000 | $251,000 | $243,000 | 13.1 |
| January | $285,000 | $247,000 | $281,000 | 15.1 |
| February | $214,000 | $226,000 | $269,000 | 14.5 |
| March | $171,000 | $219,000 | $221,000 | 11.9 |
| April | $132,000 | $205,000 | $148,000 | 8.0 |
| May | $141,000 | $198,000 | $91,000 | 4.9 |
| June | $236,000 | $212,000 | $115,000 | 6.2 |
Add three fixed items people often forget: annual insurance renewals, vehicle registrations and tax instalments on their real dates. A single $24,000 insurance renewal in May would push this example below four weeks.
Step 4: set a cash floor and mark the danger months
Pick a floor in weeks of fixed cost, for example six weeks. Mark every month where the projected closing balance falls below it. In the example, May is the problem month, and the owner knows that in November, while the bank holds nearly ten weeks.
Step 5: list the levers and test each one
For each danger month, list operating changes and estimate their effect on that month's closing balance:
- Schedule agreement tune-ups into April and May. If 300 member visits are moved from March into April and May, and each leads to some paid repair work, that revenue lands in the lean months. See service-agreement economics for how to value it.
- Take deposits on replacements at signing. A 30% deposit on $90,000 of spring installs brings $27,000 forward.
- Chase receivables before spring. If $35,000 of commercial invoices sit beyond 60 days in February, collecting them is cash you already earned.
- Plan for program payment lag. Where a utility or government program pays the installer after approval, record the expected receipt date, not the install date.
- Delay discretionary purchases. A pre-season equipment order or a new truck in April can wait for June's recovery, if supplier terms allow.
- Time marketing. Shoulder-season campaigns can fill the gap, but only if cost per booked job holds up for that kind of work.
Each lever is your decision. The calendar simply shows what each one does to the low point.
A note on growth years
Growth makes the calendar more important, not less. Adding a technician in February adds fixed cost months before that person's revenue arrives. Adding an install crew means buying equipment before customers pay. In a growth year, run the calendar twice: once as planned, and once with the new revenue arriving two months later than you hope. If the second version still stays above your floor, the plan is sound.
Step 6: roll it forward monthly
At each month-end, replace the projected numbers for that month with actual ones, add a new month at the end, and re-check the floor. Put the "weeks of fixed cost" figure on your owner dashboard so it is never more than a glance away.
Common mistakes
- Planning from invoices instead of deposits. Revenue invoiced in March may arrive in May.
- Counting a strong winter as spare cash. January's surplus is what carries May.
- Ignoring once-a-year bills. Put every annual and quarterly payment on its real date.
- Building the calendar once. A calendar that is not rolled forward is out of date in six weeks.
When to get help
If you would like the calendar built from your history and reviewed with you monthly, that is our cash-flow seasonality planning service, quoted in writing. Call, text or email with two years of month-end balances and we can tell you quickly where your low point sits.
Frequently asked questions
Can I build this from bank statements alone?
Yes. Bank statements give you actual cash in and out by month, which is what the calendar needs. Accounting reports add detail, but they are not required for a first version.
How far ahead should the calendar look?
Twelve months, rolled forward every month. The useful horizon is the next low point, which for most heating-led companies is three to six months away at any time.
Should tax payments be included?
Yes, as fixed outflows on the dates they are due. Ask your own CPA for the instalment dates and amounts; we do not give tax advice.
What is a sensible cash floor?
There is no single right number. Many owners settle on a number of weeks of fixed cost that lets them sleep at night and get through a slow spring. Agree it once, write it down and watch it.