How to Invest in Defense Stocks: Procurement, Contracts, and Key Risks

Understanding Procurement, Multi-Year Contracts, and Key Sub-Sectors Driving National Security Spending

Global security dynamics are shifting across Europe, the Indo-Pacific, and the Middle East. Many governments are reviewing military readiness and modernizing their equipment. For investors, this raises a practical question about how to invest in defense stocks. Defense budgets follow multi-year procurement cycles, so contract backlogs and government funding are key factors to understand.

This article explains how defense procurement works and highlights emerging technology priorities. It also covers key risks and how Behind the Markets looks at defense investing.

Why Defense Spending Tends to Be Long-Term

Unlike consumer goods or advertising, national defense spending is less tied to consumer discretionary cycles. Governments plan military needs several years ahead, even though Congress funds the budget each year. Once a military modernization program begins, it often spans many years of procurement, upgrades, and maintenance.

Several factors can support long-term defense demand:

• Geopolitical Realignment: Rising global competition may prompt allied nations to raise baseline defense budgets toward agreed alliance targets.

• Modernization Needs: Aging military equipment may need replacement with advanced sensor networks, low-observable materials, and connected digital command platforms.

• Maintenance Revenues: Defense platforms can stay in service for decades. Ongoing maintenance, parts replacement, and software upgrades can generate recurring cash flows.

Because defense programs run for many years, contractors often have steadier revenue visibility during economic slowdowns. Budgets can still shrink or shift, as the risks section explains.

Investors can review the Department of Defense’s FY2027 budget materials (also referred to as the Department of War) to see proposed spending. However, proposed spending is not the same as approved funding. A growing military budget does not automatically raise revenue for every contractor.

Tier-1 Prime Contractors vs. Specialized Tier-2 & Tier-3 Suppliers

When analyzing aerospace defense contractors, investors should distinguish between large system integrators and specialized component suppliers. Each group has a different risk and return profile.

Tier-1 prime contractors serve as direct lead partners to national defense ministries. These companies assemble complex platforms such as fighter aircraft, naval combatants, and armored vehicles.

Prime contractors often have steady cash flow, modest growth, and regular dividends. However, their size can limit rapid percentage growth.

In contrast, lower-tier suppliers make the subsystems that keep modern platforms working, such as radar modules, secure communications, specialized alloys, and flight control computers. Many military technology stocks fall into this group. 

Why Small and Mid-Cap Defense Suppliers May Offer Higher Growth Potential

Searches for top defense stocks to buy often lead to the largest names. However, behind major prime contractors sits a wide network of Tier-2 and Tier-3 subcontractors. These companies supply specialized components, software modules, and engineered subsystems. 

Smaller companies in this group may offer more growth potential, and some earn higher margins than primes, for several reasons:

• Proprietary Technology: Some specialized suppliers own patents in radar signal processing, thermal management, optical guidance, and radiation-hardened microelectronics, which can support higher margins.

• Multiple Customers: Some Tier-2 component makers supply parts to several competing prime platforms, which can reduce the effect of one program’s cancellation.

• Larger Contract Impact: A new $50 million component contract has a much larger percentage effect on a mid-cap company than on a mega-cap prime.

These advantages come with trade-offs. Smaller suppliers can carry higher risk than large primes, including less predictable revenue and, for some, heavy reliance on a few programs.

The table below shows how the two groups typically differ.

Table 1: General tendencies only. Individual companies vary, so check each company's filings.

The Mechanics of US Defense Procurement

US defense budget investing starts with understanding how the United States government authorizes and funds defense programs. The defense acquisition process is highly structured and regulated. It runs on a multi-year calendar, and understanding how legislation translates into corporate revenue can help investors anticipate sector cash flows.

Understanding Pentagon Budget Approvals & Multi-Year Contracts

The U.S. defense procurement process involves five stages:

1. Presidential Budget Request

The administration submits a proposed annual budget outlining defense priorities. It includes procurement, research, development, and operational spending.

2. Congressional Authorization

Congress considers the National Defense Authorization Act (NDAA). This legislation establishes defense policies and authorizes programs and spending levels.

3. Congressional Appropriations

Congress considers appropriations legislation to provide budget authority. Authorization and appropriations are separate legislative processes.

4. Contract Award

Government agencies select contractors and establish contractual requirements. These agreements specify scope, pricing, delivery schedules, and performance obligations.

Contracts awarded usually take one of two common forms:

• Cost-Plus Contracts: The government reimburses allowable company expenses plus an agreed fee. These contracts reduce contractor risk during early research and development.

• Firm-Fixed-Price Contracts: The contractor agrees to deliver equipment at a set price. Efficient execution can raise profit, but cost overruns reduce contractor margins.

Mature programs often move to fixed-price contracts. Contractors with strong cost control may earn steady margins on them, though overruns can hurt results.

5. Production and Delivery

Contractors manufacture or deliver equipment according to contractual requirements. Revenue recognition depends on the contract and applicable accounting standards.

The Congressional Research Service’s defense appropriations overview explains the difference between authorization and appropriations.

Another procurement mechanism is multi-year procurement (MYP). It lets the Department of Defense buy over several production years instead of one year at a time. It needs specific approval from Congress, so investors should check cancellation terms and annual funding requirements. 

Backlog Ratios and Book-to-Bill Ratios Explained

Equity analysts often use two key measures to evaluate revenue stability for military technology stocks:

• Funded Backlog: Backlog is the value of signed contracts not yet delivered. Funded backlog is the part where Congress has already provided money. A multi-year backlog can give visibility into future revenue.

• Book-to-Bill Ratio: This ratio compares orders received with revenue recognized over a period. A ratio above 1.0 suggests orders are outpacing deliveries.

For book-to-bill, a ratio that stays above about 1.1x for several quarters can signal a growing backlog and possible future sales growth. Conversely, a ratio below 1.0x suggests a contractor is delivering older contracts faster than it wins new ones.

Many investors also compare funded backlog with annual revenue. A backlog that covers more than a year of sales can suggest good visibility, though the right level varies by company. For illustration, a company with $2 billion in funded backlog and $1 billion in annual revenue has about two years of revenue under contract. 

Unfunded options are different: they are possible contract extensions that still need Congress to provide money. These figures are often found in a company’s 10-K and 10-Q filings on the SEC’s EDGAR database.

Key Defense Sub-Sectors to Watch

Defense priorities are shifting from traditional heavy armor toward autonomous systems, precision strike, and digital networking. Several sub-sectors are worth watching:

1. Autonomous Drones & Unmanned Systems

Unmanned aerial, surface, and sub-surface systems are changing how militaries operate. They can provide persistent reconnaissance and strike capabilities, often at lower acquisition costs than crewed platforms.

That shift may benefit companies that develop autonomous flight software, secure datalinks, and low-cost uncrewed systems. Demand could grow further as militaries adopt collaborative combat aircraft and uncrewed swarms, which rely on hardware and navigation software.

2. Hypersonics and Missile Defense

Hypersonic weapons travel faster than Mach 5 and can maneuver in flight, which makes them harder for conventional radar to track. Defense strategies emphasize both hypersonic development and advanced interceptor systems, and businesses that provide high-temperature composite materials and specialized rocket propulsion may benefit.

Space-based sensor networks are also growing. Companies that build low-earth orbit tracking sensors help detect and track hypersonic threats.

3. Cybersecurity and Military AI Hardware

Electronic warfare and cyber defense are now central areas of military activity, and defense agencies need hardened networks that can resist persistent state-sponsored attacks.

Demand is rising for tactical edge computing hardware, secure communications, and artificial intelligence tools that process battlefield sensor data in real time. Contractors that specialize in zero-trust cybersecurity architectures and anti-tamper microelectronics may also receive priority funding.

Risks Specific to Defense Investing (Budget Delays & Regulatory Scrutiny)

Defense stocks can offer revenue visibility, but they also face sector-specific risks.

Key risks in defense contracting include:

• Continuing Resolutions: Congressional budget impasses can delay new program starts and force contractors to operate under stopgap funding.

• Fixed-Price Contract Overruns: High inflation and supply chain delays can cause development costs to exceed agreed caps, eroding company margins.

• Export Control Regulations: Sales to foreign allies need government approval under the International Traffic in Arms Regulations (ITAR), which can limit international sales.

• Political Shifts: Changes in legislative priorities can lead to program cancellations, restructuring, or caps on defense spending growth.

• Valuation Risk: Defense stocks can trade at high multiples when headlines favor the sector, so a strong theme does not guarantee returns. 

The Government Accountability Office’s 2026 Weapon Systems Annual Assessment discusses acquisition delays and challenges affecting major defense programs.

Some investors try to reduce these risks by favoring companies with diversified contract bases. That does not remove the risks.

Workforce shortages are another risk. Contractors need cleared engineers and technicians for classified work, and labor bottlenecks can delay deliveries and milestone payments.

Dylan Jovine's Perspective on American Security & Defense Investing

Behind the Markets, founded by Dylan Jovine, focuses primarily on mid-cap companies with market capitalizations between $1 billion and $10 billion. Dylan has spent more than three decades in the financial industry.

Rather than focusing only on well-known prime integrators, the research team also looks at specialized mid-cap technology suppliers. These businesses sometimes develop intellectual property that larger primes rely on.

Investors interested in national security themes can review our special geopolitical research reports for detailed sector analysis. You can also follow Dylan Jovine's market commentary for ongoing observations on macro developments.

Frequently Asked Questions (FAQ) About Investing in Defense Stocks

Do defense stocks hold up in recessions?

Often, but not always. Government defense budgets rely on legislative funding rather than consumer demand, so contractor revenues can stay steadier in slowdowns. However, budgets can change, and defense stocks can still fall in broad market selloffs.

What is the difference between a prime contractor and a defense subcontractor?

A prime contractor holds the direct relationship with the government agency and manages the overall weapons system. A subcontractor supplies specialized components, software, or assemblies to the prime. Some subcontractors earn higher margins on proprietary components.

How does inflation affect defense contractors?

Inflation affects contractors differently depending on their contract mix. Under cost-plus contracts, the government generally reimburses allowable cost increases. Under firm-fixed-price contracts, contractors absorb rising labor and material costs unless the contract has adjustment clauses. Investors can check a company's fixed-price exposure during inflationary periods.

Why are backlog and book-to-bill ratios important for defense investors?

Defense programs take years to build and deliver. Backlog shows revenue already contracted for future years, which offers visibility. A book-to-bill ratio above 1.0 suggests new orders are outpacing deliveries, which can point to healthy demand.

Sources:

1. U.S. Department of Defense, FY2027 Budget Materials.

2. U.S. Congress, National Defense Authorization Act (NDAA).

3. Congressional Research Service, Defense Primer: Defense Appropriations Process (IF10514).

4. Congressional Research Service, Multiyear Procurement (MYP) and Block Buy Contracting in Defense Acquisition (R41909).

5. U.S. Securities and Exchange Commission (SEC), EDGAR database (10-K and 10-Q filings).

6. U.S. Government Accountability Office, Weapon Systems Annual Assessment 2026 (GAO-26-108457).

Disclaimer & Regulatory Disclosure: Behind the Markets is an independent financial research publisher, not a registered investment adviser or broker-dealer. The information contained in this guide is for general educational and informational purposes only and does not constitute individualized investment, financial, legal, or tax advice. Investing in aerospace and defense equities entails risk of loss, including loss of principal. Past performance is no guarantee of future results. Always consult a licensed financial advisor before making any investment decisions.