Your January was decided back in July

Quick answer: Figure out what it costs to keep your business and your household alive for one month. Look at what your slow months actually bring in. Multiply the gap by the number of slow months, and skim that total out of every busy-season check before you touch it.

Picture a siding guy in October. There's $14,000 in the checking account, the schedule's booked through Thanksgiving, and a used dump trailer on Marketplace is calling his name. He buys it. Then February shows up with two jobs on the calendar and a truck payment that didn't get the memo about the weather.

He didn't have a slow-season problem. He had a September problem. The money for February was sitting right there, and it looked like profit.

Find your floor number

Before you can save for the lean months, you need one number: what a month costs when nothing's coming in. Not what you'd like to spend. What you can't avoid.

This is an example, not a benchmark. Swap in your own figures:

• Truck payment: $780
• Commercial auto and general liability, spread monthly: $410
• Phone, scheduling software, accounting software: $150
• Storage unit for material and the trailer: $200
• What the household needs from the business to pay the mortgage and buy groceries: $4,500

Floor number: $6,040 a month.

Most guys have never added this up. They know roughly what they make in a good month and roughly what they spend, and "roughly" is where winters go wrong. Sit down with twelve months of bank statements and a highlighter. It takes an evening. It's the most useful evening you'll spend all year.

Now look at your worst months honestly

Pull your deposits by month for the last two or three years. Not invoices. Deposits, meaning what actually hit the bank. You'll see the shape of your year fast. Roofers, landscapers, painters and pool guys all have a dip, they just have it in different places. HVAC guys often get two, in spring and fall, when nobody's running anything.

Keep going with the example. Say your three slowest months average $2,500 in deposits. Against a $6,040 floor, you're short $3,540 a month. Three months of that is $10,620.

That's your slow-season number. It's not a guess and it's not a rule of thumb somebody read on a forum. It came out of your own bank account.

If you're brand new and don't have a year of history, use your floor number times three and adjust after your first winter. You'll overshoot a little. Overshooting a savings target has never ruined anybody.

Skim it while the money's loud

Divide the slow-season number by your busy months. In the example, $10,620 over seven good months is about $1,517 a month. Round it to $1,550 and don't think about it again.

The trick is timing. Move the money the day a big check clears, not at the end of the month when you "see what's left." Nothing's ever left. Money sitting in the operating account gets spent on tools, a nicer hotel on the family trip, a trailer off Marketplace.

The setup that works for most one-truck operations looks like this:

• Operating account. Customer money lands here. Bills go out from here.
• Tax account. A set percentage of every deposit, untouched until estimates are due.
• Slow-season reserve. At a different bank if you trust yourself less than you'd like to.
• Your personal account, which gets a fixed paycheck.

If that sounds familiar, it's a stripped-down version of what Mike Michalowicz lays out in Profit First. You don't need to read the whole book to get the core idea: take your cut first, run the business on what's left.

And don't confuse the reserve with tax money. The fourth-quarter federal estimated payment is due in mid-January, right in the dead of winter for a lot of trades. If you've been raiding the tax account to get through December, January hurts twice. The quarterly taxes piece covers how to keep that money walled off. For how much to set aside in your situation, ask a CPA who works with contractors. This is general education, not tax advice.

Pay yourself like an employee

This is the piece that changes your house, not just your business.

Pick a draw you can pay every two weeks, all year, including February. In the example that's the $4,500 a month for the household. Same amount in July as in January. When July brings in $19,000, you still get your paycheck and the rest stays in the business, where it does its job.

Your wife will like this more than any big month you've ever had. A household can plan around a steady number. It can't plan around a guy who's flush in August and quiet at dinner in March. Tell her the number, show her the reserve account, and let her see that winter's already paid for. That's leading your family. It beats "don't worry about it" every time.

The honest downside: it feels awful in summer. You're working 60-hour weeks and taking home the same check as in slow weeks. That's the point. The summer version of you is buying groceries for the winter version.

Fix the leaks that make winter worse

Some slow-month pain is self-inflicted months earlier.

Net-30 invoices. If you bill in October and give customers thirty days, and a few stretch it to sixty, your busy-season revenue shows up in December looking like a rescue. Collect at completion. Take cards, eat the fee, and build it into your price.

Pricing that only works eight months a year. If your rate covers your costs only when you're booked solid, no budget saves you. Run the numbers in why $45 an hour is a pay cut. Your rate has to carry twelve months of overhead on however many months you actually work.

Supply-house accounts. Pay the statement early in busy season, before they ask. It costs you nothing and it's plain decency. And when you need 60-day terms on a February job, the guy behind the counter remembers who always paid first.

What to do when it's actually slow

Saving gets you through. It doesn't fill the calendar. A few moves do.

Call your past customers. Not a mass text. A call. The people who already paid you are the cheapest leads you'll ever get, and we've made that case in before you pay for leads.

Sell next season in this season. Deck staining, gutter work, spring AC tune-ups, exterior paint. Book it in winter with a deposit and a modest early-booking discount. Two cautions. Some states limit how much of a deposit a home-improvement contractor can take, so check yours. And a deposit isn't income yet. If the job falls through, you owe it back. Don't spend it on your truck payment.

Open a line of credit before you need one. Banks lend to guys who look like they don't need money. Apply in August. A line of credit is a fine bridge when you're waiting on a check you know is coming. It's a bad way to fund a lifestyle the business can't support, and that line is one you draw yourself.

Know your no. Somebody will offer you a February job at a price that barely covers material. Taking one to keep a helper busy can make sense. Taking five because you're scared teaches the whole town your winter rate. Serve the customer well at a fair price, or pass.

Use the quiet

Here's something nobody says about a well-funded slow season: it's the only time you get to work on the business.

Rebuild the trailer lights that flickered all summer. Get the truck serviced properly. Sharpen, clean and sort every tool you own, and put borrowed ones back better than you got them. Update your pricing. Take your kids somewhere on a Tuesday, because you can.

The guy with $10,620 in the reserve account gets to rest in February. The guy who bought the trailer spends February refreshing his bank app. Same weather, same phone, same town. One of them just did his winter planning in July.