Consultant reviewing government contract at desk

FAR vs. DFARS Explained for Contractors and Subs

August 12, 2026

The Federal Acquisition Regulation (FAR) is the government-wide baseline that governs every federal contract. The Defense Federal Acquisition Regulation Supplement (DFARS) is the Department of Defense’s supplement that layers additional requirements on top of FAR. Win a DoD contract, and you must follow both.

Here is what that means in practice:

Scope: FAR applies to all executive branch agencies. DFARS applies only when DoD is the contracting agency.
When both apply: Any DoD prime contract or subcontract that includes DFARS clauses triggers both sets of rules simultaneously.
Contractor impact: DFARS adds cybersecurity obligations, domestic sourcing rules, and technical data requirements that FAR alone does not require. Flowdown clauses can bind your subcontractors to the same standards.
Immediate next step: Open the solicitation’s clause matrix and check for DFARS 252.204-7012, FAR 52.204-21, and FAR 52.244-6 before you price the job.

Key Takeaways

FAR is the government-wide baseline for all federal contracts; DFARS is the DoD supplement that adds cybersecurity, sourcing, and reporting obligations, and both apply to every DoD contract you sign.

Point	Details
FAR is the baseline	FAR governs all executive branch federal contracts; every federal solicitation incorporates FAR clauses.
DFARS adds DoD-specific rules	DFARS applies only to DoD contracts and tightens requirements for cybersecurity, domestic sourcing, and technical data.
Top clauses to scan first	Check DFARS 252.204-7012, FAR 52.204-21, and FAR 52.244-6 in every DoD solicitation before pricing.
Flowdown binds your subs	Incorporated-by-reference clauses legally bind subcontractors even when the full clause text is not printed in the subcontract.
R Construction Solutions LLC	Provides clause matrix creation, flowdown analysis, and federal bid readiness support for construction contractors nationwide.

How do FAR and DFARS differ from each other?
What is the FAR and how does it affect your contracts?
What is DFARS and what does it add to a DoD contract?
When do both apply, and what does flowdown mean for your subs?
Which specific clauses should you watch most closely?
How do you confirm which clauses apply to a specific contract?
What happens if you do not comply, and how do you reduce the risk?
A practical compliance checklist for DoD and federal bids
What contractors consistently get wrong about FAR and DFARS
Federal procurement consulting for construction contractors
Sources

How do FAR and DFARS differ from each other?

Category	FAR	DFARS
Scope	All federal executive branch agencies	Department of Defense only
Codification	Title 48 CFR, Parts 1–53	Title 48 CFR, Parts 200–299
Common clause subjects	Cost principles, socio-economic programs, small business, commercial items, reporting	Cybersecurity, domestic sourcing (Berry Amendment), technical data rights, unique identification, CMMC
Who must comply	All prime contractors; flowdown required for certain clauses	DoD primes; flowdown to subs when clause prescriptions require it
Practical contractor impact	Policy and administrative requirements	Operational requirements: SSP, incident reporting, SPRS scoring, sourcing restrictions
Penalties for non-compliance	Contract default, suspension, debarment	Same, plus False Claims Act exposure for inaccurate cybersecurity self-assessments

High-priority clauses to scan in any solicitation:

DFARS 252.204-7012 — Safeguarding covered defense information and cyber incident reporting
FAR 52.204-21 — Basic safeguarding of covered contractor information systems
FAR 52.244-6 — Subcontracts for commercial products and commercial services

Both the FAR text and the Defense Federal Acquisition Regulation Supplement are published and updated on acquisition.gov.

What is the FAR and how does it affect your contracts?

The Federal Acquisition Regulation is the government-wide procurement rulebook, codified in Title 48 of the Code of Federal Regulations. Every federal solicitation you respond to, from a General Services Administration task order to a U.S. Army Corps of Engineers construction contract, incorporates FAR clauses. Most appear by reference, meaning the solicitation lists a clause number and the full regulatory text is legally binding even if it is not printed in the document.

Common FAR clauses construction contractors encounter:

FAR 52.204-21 — Requires basic safeguarding of covered contractor information systems. Check this clause for reporting obligations before you submit a proposal; Acquisition.
FAR 52.244-6 — Governs subcontracts for commercial products and services. It specifies which FAR clauses must flow to commercial-item subcontractors and which may be tailored, giving primes a defined list to work from.
FAR 52.219-series — Small business subcontracting plans and set-aside requirements.
FAR 52.232-series — Payment terms, prompt payment, and progress payment rules.

Reading the FAR directly is straightforward. Go to acquisition.gov, select “FAR,” and browse by part or clause number. Bookmark the page; the FAR is updated through Federal Acquisition Circulars, and clause language can change between solicitation and award.

What is DFARS and what does it add to a DoD contract?

The Defense Federal Acquisition Regulation Supplement is the DoD’s agency-specific supplement to the FAR, codified in Title 48 CFR Parts 200–299. Where FAR sets the floor, DFARS raises it for defense work. When DoD is the contracting agency, both regulations apply simultaneously, and DFARS controls wherever it deviates from or adds to FAR.

Hands installing cybersecurity device onsite

DFARS frequently tightens FAR rules in three areas: cybersecurity, domestic sourcing, and technical data rights. Contractors should expect more prescriptive DoD reporting and documentation requirements than they would see on a civilian agency contract.

Key DFARS clauses to know:

DFARS 252.204-7012 — The cybersecurity clause. It requires contractors to safeguard covered defense information (CDI), report cyber incidents to DoD within 72 hours, and align their security controls with NIST SP 800-171. This clause flows to subcontractors that handle CDI.
DFARS 252.225-7001 — Buy American and Balance of Payments Program. Restricts use of foreign end products in many DoD contracts.
DFARS 252.227-7013 / 7014 — Rights in technical data and computer software. Defines what DoD can do with deliverables your firm creates.
DFARS 252.204-7019 / 7020 — NIST SP 800-171 self-assessment and posting your score to the Supplier Performance Risk System (SPRS).

The full Defense Federal Acquisition Regulation Supplement text, including clause-by-clause guidance and change notices, lives on acquisition.gov. Bookmark it. DFARS change notices publish regularly, and a clause that was optional last year may become mandatory in the next solicitation you receive.

When do both apply, and what does flowdown mean for your subs?

Every DoD prime contract incorporates both FAR and DFARS clauses. The moment you sign that prime contract, you are legally bound to both. The harder question is which of those clauses you must pass down to your subcontractors.

Flowdown is the legal mechanism by which a prime contractor extends FAR and DFARS obligations to its subcontractors. Incorporation by reference means a single line citing a clause number can legally bind a subcontractor to the full regulatory obligation, even when the clause text is not printed in the subcontract document. Many contractors do not realize this until a compliance review surfaces the gap.

Flowdown applicability depends on contract type, dollar threshold, and subject matter. There is no universal list. The Institute for Defense Analyses found that mandatory flowdowns are nearly universal in major defense acquisition programs, and that over-application of clauses can deter suppliers. Primes often flow every clause to every sub by default, which creates unnecessary burden. Careful tailoring based on contract specifics reduces that burden while preserving required protections.

Checklist for primes and subs:

Pull the prime contract’s full clause matrix and list every FAR and DFARS clause.
For each clause, check the prescription language to determine whether flowdown is mandatory, discretionary, or inapplicable to the subcontract scope.
Classify the subcontract as commercial or non-commercial. Commercial-item subcontracts have a defined, shorter list of required flowdowns under FAR 52.244-6.
Map each mandatory clause to the subcontractor’s actual work scope. A roofing sub handling no CDI does not need the full DFARS 252.204-7012 obligation, but confirm that in writing.
Document your applicability decisions. If a contracting officer or auditor questions a flowdown decision, your written rationale is your defense.

Pro Tip: Build a clause applicability matrix before contract award, not after. Discovering a mandatory cybersecurity clause post-award can add significant unbudgeted cost and create False Claims Act exposure if your SPRS score does not reflect actual compliance.

Prime contractors generally lack authority to waive regulatory flowdowns. If a sub pushes back on a clause, the prime’s best move is to identify whether the clause is truly mandatory or discretionary, then document the outcome. Plan for compliance when bidding unless the prime explicitly identifies non-mandatory clauses in writing.

Which specific clauses should you watch most closely?

Knowing the clause numbers is half the battle. Here is what each of the high-priority clauses actually requires you to do.

DFARS 252.204-7012 — Safeguarding CDI and cyber incident reporting. If your contract involves covered defense information, this clause requires a documented System Security Plan (SSP) aligned to NIST SP 800-171 Revision 3, a Plan of Action and Milestones (POA&M) for any unmet controls, and a 72-hour cyber incident report to DoD. It flows to subs that handle CDI. Action: Determine whether your contract involves CDI before bid submission. If yes, budget for SSP development and ongoing assessment.
DFARS 252.204-7019 / 7020 — NIST SP 800-171 self-assessment and SPRS. You must conduct a self-assessment against all 110 NIST SP 800-171 controls, calculate a score, and post it to the SPRS portal. An inaccurate score creates direct False Claims Act exposure. Action: Treat the SPRS score as an ongoing operational control, not a one-time form. Reassess when your IT environment changes.
CMMC context. The Cybersecurity Maturity Model Certification final rule requires third-party assessment for certain contracts. CMMC builds on NIST SP 800-171 and will be required in solicitations on a phased schedule. Action: Confirm whether the solicitation references CMMC Level 2 or 3 requirements and plan assessment timelines accordingly.
FAR 52.204-21 — Basic safeguarding of covered contractor information systems. A lighter cybersecurity clause that applies to many non-DoD contracts as well. It requires 15 basic safeguarding requirements for systems that process federal contract information. Action: Confirm your IT team has mapped these 15 controls before proposal submission.
FAR 52.244-6 — Subcontracts for commercial products and services. Defines the required and optional FAR clauses for commercial-item subcontracts. Using this clause correctly lets primes limit flowdown burden on commercial subs. Action: Classify each subcontract as commercial or non-commercial at bid stage and apply the appropriate clause list.

Linking clause obligations to your corporate policies and project budgets is not optional on DoD work. Each clause above should map to a named internal owner, a budget line, and a compliance deadline.

How do you confirm which clauses apply to a specific contract?

Use this process every time you receive a solicitation or subcontract that may involve DoD work.

Read the solicitation’s Section I (Contract Clauses) or clause matrix. This is the authoritative list of what applies. Every clause listed by number is incorporated by reference and legally binding.
Check each clause’s prescription language. The FAR and DFARS each include a “prescription” section for every clause that tells you when the clause is required, when it is optional, and when it must flow to subs. Find these at acquisition.gov.
Identify whether the contract involves Controlled Unclassified Information (CUI) or Covered Defense Information (CDI). These triggers activate DFARS 252.204-7012 and the NIST SP 800-171 obligation. If you are unsure, ask the contracting officer in writing before bid submission.
Classify each line item as commercial or non-commercial. Commercial-item classification limits the flowdown list under FAR 52.244-6. Review your commercial construction project categories to confirm how your services are classified.
Check dollar thresholds. Many FAR and DFARS clauses have minimum contract value thresholds. A clause required at $750,000 may not apply to a $200,000 subcontract.
Confirm place of performance. Some DFARS clauses apply only to work performed in the United States or at specific facility types.
Ask the contracting officer or prime contractor directly. Submit written questions during the solicitation Q&A period. For subcontracts, ask the prime to identify which clauses are mandatory versus discretionary before you sign.

At the bid stage, this review should take one to two days for a straightforward solicitation. Post-award, the same review feeds your compliance plan and budget. Assign clause review to a named person on your team, whether that is your project manager, contracts administrator, or outside counsel.

For a broader view of how government contract awards work and what to expect at each stage, the government contract awards guide covers the full timeline.

What happens if you do not comply, and how do you reduce the risk?

Non-compliance on a DoD contract is not a paperwork problem. The consequences are operational and financial.

Consequences:

Contract default or termination for cause — the government can terminate your contract and recover costs.
Suspension or debarment — you lose eligibility for future federal awards, sometimes for years.
False Claims Act exposure — submitting an SPRS score based on an inaccurate NIST SP 800-171 self-assessment is a federal civil fraud risk. Penalties can reach three times the contract value plus per-claim fines.
Lost future awards — a compliance failure on one DoD contract follows your past performance record into every subsequent bid.

High-value compliance practices:

Conduct a clause-by-clause review before signing any contract or subcontract. Legal guidance consistently recommends this as the single most effective way to avoid surprises.
Develop and maintain a documented SSP and POA&M for NIST SP 800-171. These are living documents, not one-time deliverables.
Post an honest SPRS score. If your score is negative, document your POA&M and show progress. An honest low score with a credible remediation plan is far less risky than an inflated score.
Tailor flowdowns to the actual subcontract scope rather than copying every prime clause. Contracting experts advise primes to tailor flowdowns to the specific subcontract scope, which reduces unnecessary burden on subs while preserving required protections.
Train your project managers and estimators on the clauses that affect their work. Compliance failures often start with a PM who did not know a clause existed.
Keep records. Clause matrices, flowdown logs, SSP versions, and incident response documentation are your evidence of good-faith compliance.

When to bring in outside help: if your contract involves CDI, CMMC Level 2 or 3 requirements, or a dollar value above $1 million, engage a cybersecurity consultant familiar with NIST SP 800-171 and a federal contracting attorney before you sign. The cost of that engagement is a fraction of a False Claims Act investigation.

A practical compliance checklist for DoD and federal bids

Use this checklist from bid preparation through contract award. It is built for construction contractors who are new to federal work or adding DoD contracts to an existing federal portfolio.

Register and verify SAM.gov. Confirm your registration is active, your NAICS codes are current, and your representations and certifications are accurate.
Pull the solicitation’s clause matrix. List every FAR and DFARS clause number. Flag DFARS 252.204-7012, 252.204-7019/7020, FAR 52.204-21, and FAR 52.244-6 immediately.
Classify your work scope. Determine whether your services and materials qualify as commercial items. This affects your flowdown obligations and proposal pricing.
Assess cybersecurity readiness. Do you have a documented SSP? Have you completed a NIST SP 800-171 self-assessment and posted your SPRS score? If not, budget for this before bid submission.
Build a flowdown log. For each subcontractor you plan to use, map which clauses apply, whether flowdown is mandatory, and how you will incorporate them into the subcontract.
Budget compliance costs. One-time costs include SSP development, CMMC assessment preparation, and clause matrix creation. Recurring costs include annual NIST reassessments, incident response retainers, and training. Allocate these to G&A or as direct costs depending on your accounting system.
Prepare an incident response plan. DFARS 252.204-7012 requires a 72-hour reporting window. Know who calls DoD, what gets reported, and how you preserve forensic evidence before you need to use the plan.
Create a clause matrix template. A reusable template with FAR and DFARS clause numbers, prescription references, flowdown status, and internal owners saves hours on every future bid.
Assign internal ownership. Name one person responsible for clause compliance on each contract. That person owns the flowdown log, the SSP updates, and the SPRS score.
Review subcontractor bid submissions. Before awarding subcontracts, confirm subs have acknowledged the applicable FAR and DFARS clauses. A construction bid submission checklist can help structure that review.

For budgeting, treat cybersecurity compliance as a recurring operational cost, not a one-time project. An SSP development engagement typically runs several weeks; a CMMC Level 2 assessment adds more time and cost on top of that. Build both into your overhead rate before you bid.

Rowena Tulacz brings 30+ years of operations and federal procurement consulting experience to this work, advising construction contractors on clause review, bid readiness, and compliance planning. The checklist above reflects the practical steps her clients use to move from solicitation to contract-ready without surprises.

What contractors consistently get wrong about FAR and DFARS

The most common mistake I see is treating incorporated-by-reference clauses as optional fine print. A contractor signs a subcontract, sees no clause text printed in the document, and assumes the obligation does not apply. That assumption is wrong and expensive. A one-line clause citation binds you to the full regulatory text, and “I didn’t know it was there” is not a defense in a False Claims Act investigation.

The second mistake is under-budgeting cybersecurity. Contractors who have never done DoD work routinely assume DFARS 252.204-7012 is an IT department issue they can handle with a quick checklist. In practice, a credible SSP for a 50-person construction firm with project management software, accounting systems, and field devices can take months to develop properly. Skipping that work, then submitting an SPRS score that does not reflect reality, is the fastest path to federal fraud exposure I know of. Get the score right, document the gaps, and show a credible remediation plan. That approach protects you far better than an inflated score ever will.

For primes: own the clause review before you sign the prime contract, not after you have already awarded subcontracts. For subs: ask the prime to identify mandatory versus discretionary flowdowns in writing before you price the job. If they cannot or will not, price compliance in anyway. The common contractor consulting mistakes article covers related pitfalls worth reading before your next federal bid.

Federal procurement consulting for construction contractors

Navigating FAR and DFARS compliance is manageable when you have a clear process and the right support. R Construction Solutions LLC works with construction contractors across the United States to prepare for federal and DoD contract requirements before they become problems.

R Construction Solutions LLC

R Construction Solutions LLC can help you with:

Clause matrix creation and flowdown analysis for prime contracts and subcontracts
Cybersecurity readiness coordination, including SSP intake and SPRS score preparation
Federal bid preparation, including SAM.gov registration, NAICS strategy, and RFP response support

Whether you are bidding your first DoD subcontract or adding federal work to a growing portfolio, the time to address compliance is at the bid stage, not after award. Schedule a federal procurement consulting engagement with R Construction Solutions LLC to get a clear picture of what your next federal contract will require.

Sources

Bookmark these sources. Regulations change, and the primary texts are always more reliable than secondary summaries.

Set a calendar reminder to check acquisition.gov for DFARS change notices quarterly. The NIST CSRC page for SP 800-171 is the authoritative source for any revisions to the technical control framework.

Rowena Tulacz: Construction Business Solutions | High Level CRM

Meet construction expert Rowena Tulacz. Discover how her insights enhance project management, business operations, and estimating for contractors. Learn more.

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