Accounting for Manufacturing Business: Things You Should Know

A retailer buys a product and sells it. A manufacturer buys steel, resin or fabric, pays people to turn it into something else, runs machines that wear out, and only finds out what each unit really cost once the production run is done. That extra layer is why accounting for manufacturing businesses looks so different from the books of a shop or a service company.

It has also become harder to get right. Raw material prices have swung with every new round of tariffs, and the tax rules for equipment and factory buildings have changed twice since 2025. Below, we cover the basics of manufacturing business accounting, then look at costing, inventory, recent tax changes and the mistakes we see most often.

What is Accounting for Manufacturing Business?

At its simplest, accounting for a manufacturing business follows money through the factory. You record what you spend on raw materials, what those materials are worth while they’re half-built, and what the finished products are worth sitting in the warehouse. Along the way, labour and overhead get added to each product’s cost. When it’s done well, you can look at any item you make and say what it cost to produce and how much you earned on it.

What Does an Accountant Do in a Manufacturing Company?

More than keep the books. A manufacturing accountant tracks what goes into production, from materials to wages to the power bill, and uses those numbers to help set prices. They manage budgets, keep the company on the right side of tax and reporting rules, prepare the financial statements and, where needed, handle audits. The good ones also give strategic financial advice, pointing out where the plant is losing money and what could be done about it.

What is Responsibility Accounting?

It’s a way of giving each manager ownership of their own numbers. The production manager answers for production costs. The quality control lead answers for inspection and rework. 

Maintenance has its own budget aswell. Because every cost belongs to someone, it’s much easier to see which part of the operation is running over, and to have a direct conversation about it, instead of watching total costs creep up with no clear cause.

What Type of Accounting Do Manufacturers Use?

Usually three kinds, each for a different audience. Cost accounting is for the shop floor: it breaks down what every product costs so you can find savings. Management accounting is for the owners and managers, covering budgets, forecasts and performance reports that guide day-to-day decisions. Financial accounting is for everyone outside the company. It produces the financial statements your bank, investors and the CRA rely on, prepared to recognized accounting standards.

Choosing a Costing Method

How you assign costs to products depends on what you make.

A custom cabinet shop or a machine shop building parts to order usually uses job costing. Every order gets its own file, and the materials, labour hours and a share of overhead are charged to that job. At the end, you know exactly what the Henderson order cost and whether you made money on it.

A food processor or a plastics plant running the same product all day uses process costing instead. Costs are gathered by department or stage, then divided by the number of units produced. Nobody tracks the cost of a single bottle of sauce. What matters is the cost per unit across the run.

Many manufacturers also set standard costs, a planned cost for each unit, and compare them with what actually happened. Say your standard cost for the steel in one bracket is $40, but after a price increase you’re paying $46. On a run of 5,000 brackets, that’s a $30,000 gap. Without standard costing, that loss hides inside your total cost of goods sold until year end. With it, you see the problem the month it happens and can raise prices or find another supplier.

Overhead is the part people get wrong most often. Rent, utilities, equipment depreciation and supervisors’ wages all have to be spread across production in a sensible way, usually by machine hours or labour hours. Spread them badly and some products look more profitable than they are, while others look like losers when they’re actually carrying the business.

Inventory: The Biggest Number on Your Balance Sheet

For most manufacturers, inventory is the largest asset they own, and it comes in three forms. Raw materials are what you’ve bought but not yet used. Work in progress is anything partway through production. Finished goods are ready to ship. Each needs its own count and its own value.

Work in progress is the tricky one. A half-built product already contains materials, some labour and a slice of overhead, and all of that needs to be included in its value. Leave it out and your profit for the year is understated. Overstate it and you pay tax on profit you haven’t earned yet.

The tax rule is straightforward on paper. Inventory is generally valued at the lower of what it cost you and what it’s worth today, and you have to use the same method every year. Where it pays off is old stock. Parts for a product you stopped making, or material that no longer meets spec, can often be written down to what it would actually fetch. That lowers your taxable income. Plenty of shops never bother, and those parts sit on the balance sheet at full cost for years.

And do a physical count at year end. Matching what’s on the shelves to what’s in the system is still the most reliable way to catch theft, scrap and data entry mistakes before they end up in your financial statements.

What Has Changed for Manufacturers Since 2024

Tariffs

If you buy steel or aluminum, or sell into the U.S., the last two years have been rough. Tariffs have gone on, come off and gone back on again. Right now, Canada charges counter-tariffs of 15% to 50% on more than 700 U.S. products, on top of its tariffs on U.S. steel, aluminum and cars. In August 2026 the U.S. added a 50% tariff on $27.6 billion worth of Canadian goods.

Some manufacturers are getting hit from both directions, paying more for what they buy and earning less on what they sell. The practical lesson is to update your standard costs every time a tariff changes, not once a year. If you import materials yourself, the duties also need to be recorded correctly, which is work our import export accounting team does for a number of manufacturers.

Bigger write-offs for equipment and buildings

Here’s the good news. Budget 2025 brought back the immediate 100% write-off on manufacturing machinery and equipment. It also added a new break for factory buildings. A building bought on or after November 4, 2025, and put into manufacturing use before 2030, can be written off completely in its first year, provided at least 90% of the floor space is used for manufacturing or processing. Until then, the most you could deduct was 10% a year.

The government has since proposed going even further. A “Productivity Mega Deduction”, announced in September 2026, would make immediate write-offs permanent for a wide range of assets. It hasn’t become law yet, so don’t plan a major purchase around it without checking first.

More room under SR&ED

Do you design new products, or find better ways to make existing ones? You may qualify for the Scientific Research and Experimental Development (SR&ED) credit. For Canadian-controlled private corporations, Budget 2025 doubled the spending limit for the enhanced 35% refundable credit, from $3 million to $6 million a year. Some equipment purchases qualify again too.

Tax Breaks Manufacturers Often Miss

A few savings are specific to manufacturing, and they’re easy to leave on the table.

Ontario taxes manufacturing and processing profits at a lower provincial rate than other business income: 10% instead of 11.5% on income above the small business limit. Claiming it means splitting your income between manufacturing and non-manufacturing activity on your T2 return, which requires good records of where your capital and labour are used.

Claiming the full capital cost allowance on new equipment, including the immediate write-offs above, can shift a large deduction into the year you make the purchase. Timing a major purchase just before your year end, rather than just after, can bring that deduction forward by a full year.

GST/HST paid on materials, equipment and factory costs can generally be recovered as input tax credits. With so many purchases flowing through a manufacturing business, even a small percentage of missed credits adds up. For more ways to trim costs, see our article on the power of effective accounting in manufacturing.

Let Webtaxonline Handle Your Corporate Taxes

All of this ends up in one place: your corporate tax return. For a manufacturer, the T2 has to reflect inventory valued correctly, the right capital cost allowance on every piece of equipment, the Ontario manufacturing rate, any SR&ED claim and every input tax credit you’re owed. Tax software won’t catch a missed write-down or a building that qualifies for immediate expensing. An experienced accountant for manufacturing business clients will.

At Webtaxonline, we work with manufacturers across Toronto and the GTA. We prepare and file your corporate tax return, review your costing and inventory, and look for the deductions and credits that apply to your business, so you can focus on production.

Don’t file your manufacturing company’s taxes on your own. 

Call us at 289-752-1215 or email contact@webtaxonline.ca to book a free 15-minute consultation with our manufacturing accountants.

Frequently Asked Questions

How can manufacturing business accounting improve cost control?

You can’t control a cost you can’t see. Once each product has a standard cost, you can check it against actual results every month. A jump in material prices shows up right away. So does a machine that’s scrapping more parts than it should. Proper overhead allocation adds one more insight: which products are actually paying the bills. That’s the real value of manufacturing business accounting. It gives you time to act.

What financial records should a manufacturing business maintain?

Think of it in three groups. First, anything to do with buying: supplier invoices and receiving slips. Second, anything to do with making: job sheets or batch reports, timesheets that show hours by job, and your inventory counts. Third, the usual business records, including sales invoices, bank statements, payroll, GST/HST returns and a list of your equipment and buildings. Keep all of it for at least six years, which is what the CRA generally expects. If you claim SR&ED, add project notes written while the work was happening.

When should a manufacturing business hire an accountant?

Earlier than most owners do. Once you’re holding real inventory, paying production staff or financing equipment, the books get complicated fast. And bring one in before any big move, like a new building, a major machine purchase or your first U.S. customer. The tax treatment of those decisions can change whether they make sense.

How can an accountant for a manufacturing business help with budgeting and cash flow?

The cash problem in manufacturing is timing. You pay for steel and wages today, then wait weeks or months for your customer to pay you. An accountant for a manufacturing business maps that gap with a forecast built around your production cycle. They’ll show how much cash is sitting on your shelves as inventory, and plan ahead for big outflows like equipment payments and tax installments. Department budgets, set through responsibility accounting, help each manager spot trouble early.

What accounting mistakes should manufacturing businesses avoid?

The classic one is pricing products without their share of overhead, which makes everything look more profitable than it is. Close behind: valuing work in progress wrong, leaving obsolete stock on the books for years, and forgetting to update standard costs after a supplier raises prices. On the tax side, we regularly see missed input tax credits, equipment put in the wrong capital cost allowance class, and manufacturers who never claim Ontario’s lower manufacturing rate.