How to Calculate Your SG&A Ratio Before the Board Starts Asking Margin Questions

Most COOs hit the same wall the first time they zoom in on SG&A. Operating margins have slipped a few points, gross profit is steady, and the gap is sitting in selling, general, and administrative (SG&A) expenses, which no one has reviewed since the company was half its current size.

Each percentage point of SG&A reduction adds the same point to operating margin, which is why the line gets so much attention from boards and finance teams during any margin discussion.

In this article, we explore the categories that make up SG&A, how to calculate the ratio, and the practical levers that hold beyond a one-time cost-cutting push.

In brief:

• SG&A is the non-production cost of selling and running a business, sitting below gross profit and above operating income on the income statement.
• SG&A breaks into three categories of selling, general, and administrative expenses, and the fixed-versus-variable mix determines how quickly a company can adjust spending when revenue slows.
• The SG&A ratio is total SG&A divided by net sales, with smaller companies usually running higher ratios because there's less revenue to spread fixed costs across.
• Across-the-board SG&A cuts often hit sales hardest because commissions and marketing are the easiest lines to slash, but cutting them during a growth phase usually costs more in lost revenue than the savings.
• Durable SG&A control depends on structural changes like centralized spend visibility, contract renegotiation, and growth-versus-overhead budget separation, not on one-time cuts.

What is SG&A?

SG&A is the combined cost of selling a product and running the business behind it, which means everything from advertising and sales commissions to office rent, executive pay, legal fees, and accounting costs.

Under GAAP, SG&A expenses are treated as period costs, meaning they're fully expensed in the period incurred with no assignment to individual products or deferral into future periods.

On the income statement, SG&A sits below gross profit and above operating income, which is the structural detail that makes SG&A the most-reviewed line at most board meetings I've sat in.

Every dollar of SG&A reduction flows straight to operating income, and the operators I work with usually find that if gross margins look healthy. Still, operating margins are weak, SG&A is the gap, and it's been the gap for longer than anyone realized.

What are the differences between SG&A and operating expenses?

The biggest difference is that SG&A is a subset of operating expenses, not a separate category, which trips up more finance teams than it should. Operating expenses include every cost a company incurs in day-to-day operations, except for the cost of goods sold. SG&A falls within that bucket alongside R&D, depreciation on non-production assets, and other operating expenses.

The second difference you should know is that leadership tracks operating expense as the total cost-to-run number, while SG&A is the sub-bucket finance teams target when looking for margin levers.

Here’s where each cost category sits and how it's treated:

Take a bakery as an example. Flour, sugar, baker wages, and oven maintenance are COGS because they scale with the amount of bread the bakery produces. At the same time, the owner's salary, marketing spend, and office rent are SG&A because they don't vary with output.

Getting this classification wrong distorts gross profit margin, operating margin, and how the company benchmarks against industry peers, and it's the kind of detail that becomes a problem at the worst possible time if it's been wrong for several quarters.

The categories and the difference from operating expenses set up the next question every operator I work with asks: how to measure SG&A and what a healthy ratio looks like.

Types of SG&A

SG&A breaks into three categories, and each one moves at a different speed when revenue changes, which is the part most finance teams underestimate when they start cost-cutting.

You should know about these three categories:

• Selling expenses: Costs tied to generating revenue, including sales commissions, salesperson salaries, advertising, marketing, trade shows, and travel for the sales team. Commissions vary with sales volume, while salesperson salaries are semi-fixed.
• General expenses: Overhead costs that keep the business running, such as rent, utilities, insurance, and office supplies. These are mostly fixed and don't change based on how much the company sells.
• Administrative expenses: The cost of governance and back-office operations, including executive salaries, accounting and legal fees, HR, and professional consultants. These are also mostly fixed.

The fixed-versus-variable mix inside SG&A is the part I push every operator to understand before any cost-cutting conversation. This is because a company with SG&A dominated by fixed costs like rent and executive salaries has much less room to adjust spending quickly during a downturn than one with more variable selling expenses.

When revenue slows, that mix shows whether the company can reduce costs at the same pace or is stuck carrying overhead through the trough.

How to calculate and report SG&A

The SG&A ratio expresses total SG&A as a percentage of net sales and is one of the most closely watched operating metrics in any financial review. Calculating it is straightforward, but interpreting it correctly is where most teams I work with run into trouble. This is because the right benchmark depends on industry, company size, and growth stage.

I’ll discuss four steps that cover the formula, the components, a worked example, and how to interpret the result against what good looks like.

1. Identify what counts as total SG&A

The line items that count toward total SG&A typically include the categories below, with the depreciation question worth flagging because it's where I see most companies misclassify costs:

• Selling expenses: Commissions, salesperson salaries, and advertising costs
• General expenses: Rent, utilities, and insurance
• Administrative expenses: Executive pay, legal fees, and accounting costs
• Non-production depreciation: Office furniture, computers, and administrative buildings

Add these together before applying the formula, and double-check that production-related depreciation (manufacturing equipment, factory buildings) sits in COGS rather than SG&A, because that classification is the most common mistake I see in income statement reviews.

2. Know the formula

The SG&A ratio measures how many cents of every revenue dollar go toward selling and running the business, with production costs measured separately in COGS.

The formula is:

• SG&A ratio = (Total SG&A expenses / Net sales) × 100, with total SG&A pulled directly from the income statement below gross profit.

The wrinkle worth knowing is that companies don't all report SG&A the same way. Some show it as a single line, while others, especially SaaS businesses, break it into "Sales & Marketing" and "General & Administrative" separately.

The first thing I do when comparing a company's ratio to a peer's is to check how each company groups its operating costs. This is because two companies with identical operations can report SG&A ratios that appear meaningfully different due solely to classification choices.

3. Work through an SG&A ratio example

Take a company generating $5 million in annual revenue:

• Selling expenses (sales salaries, commissions, advertising) total $400,000
• General expenses (rent, utilities, insurance) come to $300,000
• Administrative expenses (executive pay, legal, accounting) add another $350,000

Total SG&A lands at $1,050,000, and the SG&A ratio is $1,050,000 / $5,000,000 × 100 = 21%.

That 21 cents of every revenue dollar goes toward non-production costs is the headline number, but the more useful question is what the company looked like at this ratio twelve months ago.

The teams I work with that catch margin erosion early are the ones tracking SG&A ratio quarter over quarter rather than treating it as an annual exercise, because a 21% ratio that climbed from 18% over four quarters tells a much different story than a stable 21% ratio.

4. Read the result against what good looks like

A "good" SG&A ratio depends almost entirely on industry and company size, with smaller companies usually running higher ratios because there's less revenue to spread fixed costs like rent and executive salaries across.

Trend direction matters more than the absolute number. If revenue grew 25% in a year while SG&A grew 35%, the company's operating efficiency is slipping even though the absolute ratio might still look healthy.

The breakdown I push every operator to track is to separate selling and G&A expenses into separate lines rather than a combined SG&A number, because the combined ratio hides whether spending is fueling growth or covering overhead.

If a board member asks what the business would look like without the current sales and marketing investment, the finance team should be able to answer in two minutes, and that's only possible when the G&A ratio is being tracked separately from total SG&A.

With the math in place, the next question is what moves SG&A in a way that holds over multiple quarters.

Best practices to manage and control your SG&A expenses

Durable SG&A control depends on structural changes that hold beyond the first cost-cutting push, not on one-time line-item cuts. The five practices below are the ones I push every operator to implement before any board meeting that will raise margin questions.

Centralize spend visibility

The pain point I see most often is that SG&A spend lives across spreadsheets, bank feeds, and email approvals, so basic questions like which vendor costs increased last quarter can't be answered until after month-end close.

A financial automation platform with real-time transaction visibility, automatic GL categorization, per-department budget controls, and pre-purchase policy enforcement closes that gap. It gives the finance team current data before SG&A creep becomes visible on the P&L.

Set a regular expense review cadence

The pain with SG&A creep is that no single cost increase ever looks big enough to act on, so it accelerates between reviews when no one is checking recurring charges against usage.

The cadence I push is a monthly recurring-charge audit plus a quarterly departmental spend-versus-budget review, with a written explanation required for any category running more than 10% off plan.

The three questions worth asking of every line item are whether anyone uses it, whether it overlaps with another spend, and when the contract was last renegotiated.

Renegotiate vendor contracts before auto-renewal

The pattern I see most often is vendor pricing climbing through silent auto-renewals, with no one having had a renewal conversation in months. Start renewal discussions well before expiration and, where possible, compare competing bids.

Vendor pricing rarely decreases on its own, and reviewing accounts payable patterns by vendor can surface where the increases are hiding. Consolidating overlapping vendors increases buying power, and a longer commitment can sometimes secure better pricing on services with predictable usage.

Separate growth SG&A from overhead SG&A in your budget

Another mistake I see most often is across-the-board cost cuts that hit sales hardest because commissions and marketing are the easiest lines to slash, even though cutting them during a growth phase usually costs more in lost revenue than the savings.

Building the budget with selling and G&A expenses as separate line items gives leadership a clearer answer when the "cut" question comes up. This follows the rule of thumb that selling expenses should scale with the revenue plan, while G&A should stay flat or grow more slowly than revenue.

Audit real estate costs

The line operators routinely under-review is real estate, even though facilities consistently rank among the largest non-people cost lines in a company's SG&A budget. The check I push every operator to run measures space utilization using badge data or desk booking records.

If a meaningful share of leased space goes unused on a given day, subleasing or renegotiating lease terms can produce real savings before the next renewal lands.

Take control of your SG&A

SG&A often grows quietly. A new subscription here, an uncontested vendor renewal there, and suddenly operating margins look worse than two quarters ago with no clear explanation in any single line item.

The pattern I see most often is that the finance team doesn't have the visibility to catch the creep until it's already moved several points of margin. A financial platform that connects expense management, per-department budget limits, vendor spend analysis, and accounting integrations into a single view closes that gap before SG&A becomes a board question.

Modern spend management platforms like Ramp give finance teams that real-time visibility at the point of transaction, which is the difference between catching SG&A creep early and explaining it to the board after the fact.

Frequently asked questions about SG&A

Is depreciation included in SG&A?

Depreciation on non-production assets like office furniture, computers, and administrative buildings is typically included in SG&A. Depreciation on manufacturing equipment or production facilities belongs in COGS instead, with the allocation depending on whether the asset supports production or general business operations.

What is a good SG&A ratio for a small company?

Smaller companies usually run higher SG&A ratios because there's less revenue to spread fixed costs across. The signal worth watching is direction more than the absolute number, because a declining ratio as the company grows is the clearest sign of improving operating efficiency.

How often should you review SG&A expenses?

The cadence I push every finance team toward is monthly reviews of recurring charges and subscriptions, plus quarterly departmental budget reviews and an annual zero-based review of discretionary categories. The annual deep review is what prevents cost creep from building quarter over quarter.

Can SG&A expenses be capitalized?

SG&A expenses are treated as period costs under GAAP, meaning they're expensed in the period incurred and generally aren't capitalized or deferred. Capital expenditures, such as equipment purchases, follow different rules and appear on the balance sheet as assets rather than on the income statement.