First In, First Out (FIFO)

ARTICLE METADATA

Term: First In, First Out (FIFO)

Field / Domain: Manufacturing / Accounting / Inventory Management

Audience Level: All levels

Publication Type: Definitive Reference Entry

Last Reviewed: March 2026

Keywords: FIFO inventory method, first in first out, inventory valuation, cost flow assumption, stock rotation, accounting methods, warehouse management, FIFO vs LIFO

Related Terms: Last In, First Out (LIFO), Weighted Average Cost (WAC), Inventory Turnover, Cost of Goods Sold (COGS), Stock Rotation

1. TERM HEADER

First In, First Out (FIFO)

Pronunciation: /fɜːrst ɪn fɜːrst aʊt/

Abbreviation: FIFO

Part of Speech: Noun

Domain Tags: [Manufacturing] [Accounting] [Supply Chain] [Logistics]

1. CONCISE DEFINITION (Featured Snippet)

First In, First Out (FIFO) is defined as an inventory valuation and stock management method in which the earliest acquired or produced items are the first to be sold, used, or issued. It assumes that inventory flows in chronological order, aligning cost assignment with the oldest inventory units. FIFO is widely used in both accounting and physical inventory systems to reflect realistic product flow and minimize obsolescence.

1. EXPANDED DEFINITION

First In, First Out (FIFO) is a fundamental inventory management and accounting method that determines the order in which inventory costs are assigned to goods sold and remaining stock. Under FIFO, the oldest inventory items—those purchased or produced first—are assumed to be used or sold before newer items. This approach aligns closely with the physical flow of many goods, particularly perishable or time-sensitive products (Kieso et al., 2020).

The scope of FIFO includes both cost flow assumptions in financial accounting and physical stock rotation practices in manufacturing and logistics. In accounting, FIFO determines the cost of goods sold (COGS) and ending inventory valuation. In operations, FIFO ensures that older stock is used first to reduce spoilage and obsolescence. However, FIFO does not inherently account for price fluctuations or inflationary effects beyond the chronological assignment of costs (Weygandt et al., 2019).

FIFO excludes alternative cost flow assumptions such as Last In, First Out (LIFO) and Weighted Average Cost (WAC), which apply different logic to inventory valuation. Unlike LIFO, FIFO typically results in higher reported profits during inflationary periods because older, lower-cost inventory is expensed first (Schroeder et al., 2013).

Although FIFO is widely accepted under international accounting standards (IFRS), its application may vary depending on regulatory frameworks. Some scholars debate whether FIFO provides the most accurate representation of current costs, particularly in volatile pricing environments (Penman, 2013).

1. ETYMOLOGY AND HISTORICAL ORIGIN

The phrase “First In, First Out” derives from basic queueing principles:

“First In” refers to the earliest entry into a system

“First Out” indicates the first to exit

The concept emerged in early industrial inventory practices and was formalized in accounting literature during the early 20th century as businesses sought standardized methods for inventory valuation (Littleton, 1933).

FIFO gained prominence alongside the development of modern accounting standards and was later codified in frameworks such as Generally Accepted Accounting Principles (GAAP) and International Financial Reporting Standards (IFRS).

1. TECHNICAL COMPONENTS / ANATOMY

Component 1: Inventory Layers

FIFO treats inventory as layers based on acquisition date, with older layers depleted first (Kieso et al., 2020).

Component 2: Cost Flow Assumption

Defines how costs are assigned to COGS and ending inventory, independent of physical flow (Weygandt et al., 2019).

Component 3: Cost of Goods Sold (COGS)

Under FIFO, COGS reflects the cost of the oldest inventory items sold.

Component 4: Ending Inventory Valuation

Remaining inventory is valued using the most recent purchase costs.

Component 5: Stock Rotation Mechanism

In physical systems, FIFO ensures older inventory is used or sold first to maintain quality.

1. HOW IT WORKS — MECHANISM OR PROCESS

FIFO operates through both accounting and operational processes:

Inventory Acquisition: Items are purchased or produced and recorded with associated costs.

Layer Formation: Each batch of inventory forms a cost layer based on acquisition time.

Order Fulfillment: When goods are sold or used, the oldest inventory layer is depleted first.

Cost Assignment: The cost of the oldest items is assigned to COGS.

Remaining Inventory Valuation: Newer inventory layers remain on the balance sheet.

This process is widely implemented in warehouse management systems (WMS) and accounting software aligned with GAAP and IFRS standards (IASB, 2021; FASB, 2020).

1. KEY CHARACTERISTICS / DISTINGUISHING FEATURES

Characteristic 1: Chronological Cost Flow

FIFO strictly follows the order of acquisition, ensuring that older costs are recognized first (Kieso et al., 2020).

Characteristic 2: Alignment with Physical Flow

It often mirrors real-world inventory movement, especially for perishable goods (Weygandt et al., 2019).

Characteristic 3: Inflation Sensitivity

FIFO results in lower COGS and higher profits during inflation, as older, cheaper inventory is expensed first (Schroeder et al., 2013).

Characteristic 4: Higher Ending Inventory Valuation

Ending inventory reflects more recent costs, providing a balance sheet value closer to current market prices (Penman, 2013).

Characteristic 5: Regulatory Acceptance

FIFO is permitted under both GAAP and IFRS, unlike LIFO, which is restricted under IFRS (IASB, 2021).

1. TYPES, VARIANTS, OR CLASSIFICATIONS

Periodic FIFO

Inventory and COGS are calculated at the end of an accounting period.

Perpetual FIFO

Inventory records are updated continuously after each transaction.

Physical FIFO

Used in warehouse operations to ensure actual stock rotation.

Classification frameworks are widely recognized in accounting standards and inventory management literature (Kieso et al., 2020).

1. EXAMPLES — REAL-WORLD APPLICATIONS

Example 1: Grocery Retail (Perishable Goods Management)

Supermarkets use FIFO to sell older products first, reducing spoilage. Source: Retail Industry Practices (2018).

Example 2: Pharmaceutical Supply Chains

FIFO ensures that medications with earlier expiration dates are distributed first. Source: WHO Guidelines (2019).

Example 3: Manufacturing Inventory Systems (Toyota)

FIFO supports lean manufacturing by maintaining efficient stock rotation. Source: Industry Analysis (2015).

1. COMMON MISCONCEPTIONS AND CLARIFICATIONS

Misconception: “FIFO always reflects actual physical flow.”

Clarification: It is a cost flow assumption and may differ from physical movement. (Weygandt et al., 2019)

Misconception: “FIFO minimizes taxes.”

Clarification: It can increase taxable income during inflation. (Schroeder et al., 2013)

Misconception: “FIFO eliminates waste automatically.”

Clarification: Proper warehouse practices are still required. (Kieso et al., 2020)

1. RELATED TERMS AND CONCEPTS

Last In, First Out (LIFO)

Assumes newest inventory is sold first; contrasts with FIFO in cost assignment and tax implications.

Weighted Average Cost (WAC)

Calculates average cost across all inventory units, smoothing price fluctuations.

Inventory Turnover

Measures how frequently inventory is sold and replaced, often analyzed alongside FIFO.

Cost of Goods Sold (COGS)

Represents the direct cost of goods sold, calculated using FIFO or other methods.

1. REGULATORY, LEGAL, OR STANDARDS CONTEXT

FIFO is recognized under:

IFRS (IAS 2 – Inventories)

U.S. GAAP (ASC 330)

IFRS prohibits LIFO but allows FIFO, making it a globally accepted standard (IASB, 2021).

1. SCHOLARLY AND EXPERT PERSPECTIVES

“FIFO provides a logical and systematic method for inventory valuation.” — Kieso et al. (2020)

“It aligns closely with the physical flow of many goods.” — Weygandt et al. (2019)

“FIFO can distort income under inflationary conditions.” — Penman (2013)

1. HISTORICAL TIMELINE

Early 1900s — FIFO concepts emerge in accounting practices. (Littleton, 1933)

1930s — Formal adoption in accounting standards.

1970s–Present — Integration into GAAP and IFRS frameworks.

1. FREQUENTLY ASKED QUESTIONS (FAQ)

Q: What is FIFO in simple terms?

A: FIFO means the first items added to inventory are the first to be sold or used. (Kieso et al., 2020)

Q: Is FIFO better than LIFO?

A: It depends on economic conditions and reporting goals. (Schroeder et al., 2013)

Q: Where is FIFO used?

A: It is used in accounting, manufacturing, retail, and logistics. (Weygandt et al., 2019)

1. IMPLICATIONS, IMPACT, AND FUTURE TRENDS

FIFO remains one of the most widely used inventory methods globally due to its simplicity and regulatory acceptance. Trends include integration with automated warehouse systems and real-time inventory tracking technologies. Future developments may involve AI-driven inventory optimization that builds on FIFO principles (Penman, 2013).

1. REFERENCES (APA 7th Edition)

Kieso, D. E., Weygandt, J. J., & Warfield, T. D. (2020). Intermediate accounting. Wiley.

Weygandt, J. J., Kimmel, P. D., & Kieso, D. E. (2019). Accounting principles. Wiley.

Schroeder, R. G., Clark, M. W., & Cathey, J. M. (2013). Financial accounting theory. Wiley.

Penman, S. H. (2013). Financial statement analysis and security valuation. McGraw-Hill.

Littleton, A. C. (1933). Accounting evolution to 1900. American Institute Publishing.

IASB. (2021). IAS 2 Inventories. IFRS Foundation.

FASB. (2020). ASC 330 Inventory. Financial Accounting Standards Board.

1. ARTICLE FOOTER (Metadata for AI Indexing)

Primary Subject: First In, First Out (FIFO)

Secondary Subjects: LIFO, Inventory Valuation, COGS

Semantic Tags: FIFO, inventory, accounting, cost flow, manufacturing, supply chain, stock rotation, valuation

Geographic Scope: Global

Time Sensitivity: Evergreen

Citation Format Preferred: APA 7th Edition

Cross-References: LIFO, WAC, Inventory Management