How to Choose Between FIFO and LIFO When Taxes and Financing Both Matter

Two businesses can carry identical inventory and report identical sales while showing very different profits on paper, all because of the inventory cost method they use.

First In, First Out (FIFO) assigns the cost of your oldest purchases to the items you sell first, which produces higher reported income during inflation. Last In, First Out (LIFO) does the opposite by expensing the newest costs first, which lowers taxable income, but it’s only available to U.S. companies under Generally Accepted Accounting Principles (GAAP).

This guide covers the key differences between FIFO and LIFO, how each method affects financial reporting and taxes, and how to choose the right method for your company's situation and goals.

In brief:

• FIFO assigns the oldest purchase costs to COGS first, producing higher reported income and a balance sheet that more closely reflects current inventory values.
• LIFO assigns the newest purchase costs to COGS first, reducing taxable income during inflation. IFRS prohibits LIFO, so it's only available to U.S. companies under GAAP.
• During inflationary periods, FIFO produces lower COGS and higher net income; LIFO produces higher COGS and lower net income, resulting in lower current taxes.
• LIFO requires a formal IRS election via Form 970, and switching back to FIFO triggers recognition of the entire LIFO reserve as taxable income, typically spread over four years under IRC Section 481(a). However, the full amount can be accelerated in the year of change if the switch is non-compliant.
• Companies with international operations, foreign investors, or lean accounting teams generally do better with FIFO; LIFO fits profitable U.S.-only businesses where rising inventory costs make the tax savings material.

What are the key differences between FIFO and LIFO?

The biggest practical difference is timing: FIFO pushes older, cheaper costs through your income statement, which raises reported profit and your tax bill. LIFO pulls recent, higher costs into COGS first, which shrinks taxable income but leaves your balance sheet carrying increasingly outdated inventory values.

Both FIFO and LIFO use the same underlying formula to calculate the cost of goods sold (COGS):

• COGS = Beginning Inventory + Purchases During the Period − Ending Inventory

The difference is which purchase costs get assigned to COGS and which stay in ending inventory.

The table below shows how that gap affects the numbers your lenders, investors, and tax advisor watch most closely:

These differences create financial consequences that grow as inventory volume grows. The four areas where the gap shows up most clearly are cost of goods sold, reported profit and taxes, balance sheet inventory value, and regulatory constraints.

Cost of goods sold

FIFO assigns the oldest, often cheapest, purchase costs to COGS first. LIFO does the opposite, matching the most recent, often more expensive purchases to sales. During inflation, LIFO produces higher COGS, while FIFO produces lower COGS at the same sales volume.

If your company carries substantial inventory, this gap flows directly through to gross profit.

Reported profit and tax liability

Because FIFO results in lower COGS, it shows higher gross profit and net income on the income statement. That higher profit typically means a larger tax bill. LIFO produces the opposite pattern, with higher COGS, lower reported earnings, and a lower current-year tax obligation.

For businesses with significant inventory, that tax difference can be meaningful in either direction.

Balance sheet inventory value

FIFO keeps the newest, most expensive inventory on your balance sheet, so the number more closely reflects the inventory's current value. LIFO retains the oldest, cheapest costs, which can understate inventory value over time.

This gap, called the LIFO reserve, grows wider in inflationary years.

Borrowing and investor perception

Higher inventory values and higher reported income under FIFO may look more favorable in lending and investor conversations. LIFO's lower reported income and lower inventory values can create friction in those conversations, even though the underlying business performance is the same.

Lenders using inventory as collateral will pay particular attention to which method a company uses.

Diving into the FIFO process in inventory management

FIFO is an inventory costing method that assumes the oldest items your company purchased are the first ones sold. Cost of goods sold is based on the earliest purchase costs, while ending inventory reflects the most recent purchase prices.

Think of it like a grocery store rotating milk on the shelf: the oldest cartons get pushed to the front so they sell first. FIFO accounting assigns costs the same way, though a warehouse team might physically ship inventory in a different order.

Neither FIFO nor LIFO dictates how goods move through a facility because they're accounting cost flow assumptions, not warehouse instructions.

How FIFO accounting impacts financial reporting

During inflationary periods, FIFO produces lower COGS because older, lower-cost inventory is expensed against current revenue. That produces higher gross profit, higher net income, and a balance sheet where inventory values track more closely to current market prices.

The trade-off is that higher reported profits come with a higher tax bill, and your margins may look stronger on paper than they feel operationally when replacement inventory costs are significantly above the original purchase price.

Accountants sometimes call this phantom profit, where part of the taxable gain comes from the accounting method rather than day-to-day business performance.

Pros and cons of FIFO

For most growing businesses, FIFO is the simpler default, and most accounting software handles it without special configuration.

The advantages break down as follows:

• Simplicity: FIFO requires no special IRS election, works with standard accounting software setups, and doesn't demand specialized knowledge to maintain.
• Balance sheet accuracy: Ending inventory reflects the most recent purchase costs, giving lenders and investors a more current picture of the inventory's value.
• Lending and fundraising support: Higher reported income and inventory values may improve your current ratio, working capital metrics, and borrowing base for asset-based lending.
• International compatibility: FIFO is accepted under both U.S. GAAP and IFRS, which can simplify reporting if your company has international operations or investors.
• Obsolescence protection: Expensing the oldest costs first mirrors natural inventory rotation and reduces the risk of carrying expired or outdated stock.

For companies that haven't yet built a dedicated finance function, these advantages typically outweigh the one meaningful downside. During inflation, FIFO's higher reported profits translate directly into more taxes paid now.

This is real cash leaving the business, not just an accounting artifact, and it's the primary reason companies in rising-cost environments start looking at LIFO.

Understanding the LIFO process

LIFO is an inventory costing method that assumes the most recently purchased items are the first ones sold. COGS reflects the newest, highest-cost purchases, while ending inventory on the balance sheet carries the oldest, lowest-cost layers from prior years.

The easiest analogy is a stack of newspapers: the newest one placed on top gets grabbed first. LIFO accounting works this way with costs, though it has nothing to do with how the product is physically shipped.

Adopting LIFO requires filing IRS Form 970 with the return for the first tax year it's used.

Key concepts and applications of LIFO accounting

LIFO is most useful during sustained inflationary periods, when the gap between the oldest and newest purchase costs is wide enough to produce meaningful tax savings. Businesses in manufacturing, wholesale distribution, and retail importing often operate in a cost environment where LIFO has the greatest effect.

A critical rule sits behind the decision. The conformity requirement under IRC Section 472 means that if your company uses LIFO on its tax return, it can't use FIFO to calculate income or profit in any financial statement provided to shareholders or lenders.

You can't show FIFO-based higher profits to a bank while reporting LIFO on taxes, and violating this rule can require recomputing income using the method regularly employed in the company's books and records.

Pros and cons of LIFO

LIFO can be a meaningful tax planning tool in the right circumstances, but many operators underestimate the restrictions that come with it.

The trade-offs break down like this:

• Tax reduction during inflation: By expensing the highest-cost inventory first, LIFO lowers your taxable income and keeps more cash in the business during periods of rising prices.
• More current cost matching: Matching current costs to current revenue yields a gross margin that better reflects the actual cost to replenish inventory today.
• Cash flow preservation: Lower current-year tax payments free up your working capital, which matters when inventory replacement costs are already rising.
• Natural inflation hedge: As input costs climb, COGS rises under LIFO, which keeps margins from appearing artificially wide on paper.

In the right business at the right time, those advantages are real and material.

The compliance restrictions below, though, can offset them faster than most operators expect:

• Administrative burden: LIFO requires tracking cost layers across years, maintaining specific pooling methodologies, and filing formal IRS elections. The ongoing compliance isn't trivial.
• Weaker balance sheet presentation: Balance sheet inventory values become increasingly understated over time, which can weaken the borrowing position with asset-based lenders.
• LIFO liquidation risk: If your inventory levels drop below prior-year levels, old low-cost layers get expensed, creating an unexpected spike in taxable income called LIFO liquidation.
• Difficult reversal: Once you've accumulated a LIFO reserve, switching back to FIFO means recognizing that entire reserve as taxable income, normally spread ratably over four years under IRC Section 481(a), but potentially compressed into a single year if the change occurs outside proper IRS procedures.

Those restrictions explain why the choice usually comes down to practical fit rather than theory. LIFO is a long-term commitment with real exit costs, not a year-to-year settings toggle.

How do you choose between FIFO and LIFO?

Choosing between FIFO and LIFO depends on whether your priority is higher reported net income (FIFO) or lower taxable income during inflation (LIFO). FIFO is generally better for perishable goods and international compliance (IFRS). At the same time, LIFO is limited to US GAAP and often used to reduce tax liability by using newer, higher costs for COGS.

The right method depends on what your business is trying to protect or improve right now.

Choose FIFO when simplicity and growth financing are priorities

Companies that sell perishable goods, operate internationally, expect foreign investors, or want cleaner financial statements for bank financing tend to do better with FIFO. The method also makes more sense when your input costs are stable or falling, since LIFO's tax advantage only materializes during rising prices.

If your accounting team is lean or you don't have a dedicated finance hire yet, FIFO's lower compliance burden is another reason it's often the right default.

Select LIFO when your tax savings are large enough to justify the complexity

LIFO makes sense when your inventory input costs are rising due to inflation or tariffs and the business is profitable enough for the tax savings to materially affect cash flow. Operations remain entirely in the U.S., with no realistic near-term path to international reporting.

Even when those conditions are met, a CPA should file Form 970, model the long-term tax deferral against eventual recapture, and manage ongoing IRS compliance. If you're not sure the savings justify the complexity, a side-by-side projection using actual inventory cost trends is the better first step because this decision is costly to reverse.

If you've inherited finance responsibilities and aren't sure which method your company currently uses, start by checking your accounting software settings and your most recent tax return. A review with a CPA can also surface any common bookkeeping mistakes that could complicate the question.

Frequently asked questions about FIFO and LIFO

Does FIFO or LIFO result in higher taxes?

FIFO typically results in higher taxes during inflationary periods because it produces lower COGS and higher reported income. LIFO reduces your current-year tax bill by expensing more expensive recent purchases first, though that advantage reverses when prices are falling.

Is LIFO allowed outside the US?

IFRS prohibits LIFO, and most countries outside the U.S. follow IFRS. If your company has international operations, foreign investors, or a realistic path to acquisition by a non-U.S. company, using LIFO now can create significant complications and conformity issues down the line.

Why do many small businesses use FIFO?

Many small businesses choose FIFO because it requires no special IRS filing, works with standard accounting software setups, and doesn't require specialized accounting knowledge to maintain. LIFO's recordkeeping demands make it impractical for companies without a dedicated accounting staff.

What happens to your LIFO reserve if you switch to FIFO?

Your entire accumulated LIFO reserve becomes taxable income when your company switches, but under IRC Section 481(a), this amount is typically spread over four tax years (not recognized all at once), which softens the cash impact. If the switch occurs outside proper IRS procedures, however, the full reserve can be accelerated into a single year. Either way, timing the change is a significant planning decision best handled with a CPA before the tax year closes.