How to Write SOPs: The Complete Standard Operating Procedure Guide
A practical guide to writing clear, effective SOPs — covering formats, essential sections, writing style, common mistakes, and how to review SOPs for completeness before approval.
A standard operating procedure (SOP) is a step-by-step document that tells someone exactly how to perform a task. When SOPs are clear, teams work consistently. When SOPs are vague, people improvise — and inconsistency, errors, and compliance failures follow.
The irony: most SOPs are poorly written. They're created by subject matter experts who know the process so well that they skip steps, use jargon without definitions, and assume knowledge the reader doesn't have. The result is a document that only makes sense to the person who wrote it.
This guide covers how to write SOPs that people actually follow — including formats, essential sections, writing style, common mistakes, and how to review SOPs before they go into production.
What Is an SOP and Why Does It Matter?
An SOP is a documented, repeatable procedure for performing a specific task or process. It exists to ensure:
- Consistency — everyone performs the task the same way
- Quality — the output meets a defined standard every time
- Compliance — regulatory and internal requirements are met
- Training — new staff can learn processes without relying on tribal knowledge
- Continuity — processes survive staff turnover
SOPs are required across virtually every regulated industry: healthcare, manufacturing, pharmaceuticals, food production, financial services, aviation, and government. Even in unregulated industries, SOPs reduce errors, speed up onboarding, and provide a foundation for process improvement.
SOP Formats
There are three main SOP formats. Choose based on the complexity of the procedure:
1. Simple Step List
Best for straightforward, linear procedures with no decision points.
Example: Processing a Customer Refund
- Log into the refund management system
- Search for the customer's order by order number or email
- Verify the refund eligibility against the refund policy (Section 4.2)
- Select "Issue Refund" and choose the refund method (original payment method)
- Enter the refund amount and reason code
- Submit for manager approval if the refund exceeds $500
- Confirm the refund and send the customer notification email
2. Hierarchical Steps
Best for procedures with sub-steps or conditional actions within a linear flow.
Example: Onboarding a New Employee
-
Pre-arrival setup (HR Manager, 5 days before start) 1.1. Create employee record in HRIS 1.2. Generate system access credentials 1.3. Order equipment (laptop, phone, access card) 1.4. Send welcome pack email with Day 1 instructions
-
Day 1 orientation (HR Coordinator) 2.1. Meet employee at reception at 9:00am 2.2. Complete ID verification and emergency contact forms 2.3. Issue access card and equipment 2.4. Conduct office tour (30 minutes) 2.5. Introduce to direct manager
-
First week training (Direct Manager) 3.1. Review role responsibilities and KPIs 3.2. Assign onboarding buddy 3.3. Schedule system training sessions 3.4. Set 30/60/90-day objectives
3. Flowchart Format
Best for procedures with multiple decision points where different paths lead to different outcomes.
Use flowcharts when:
- The procedure involves yes/no decisions that change the next step
- Multiple roles interact within the same process
- The procedure has exception handling paths
- A visual representation is clearer than written steps
Flowcharts are typically created alongside a written SOP, not instead of one. The flowchart provides the overview; the written SOP provides the detail.
Essential SOP Sections
Every SOP should include these sections, regardless of format:
| Section | Purpose | Content |
|---|---|---|
| Title | Identify the procedure | Clear, specific title (not "Procedure 47") |
| SOP Number/ID | Unique identification | Follows your organisation's numbering system |
| Version and Date | Track revisions | Current version number, effective date, last review date |
| Purpose | Why this SOP exists | 1-2 sentences explaining what the SOP achieves |
| Scope | What's covered and what isn't | Which processes, departments, or situations this SOP applies to |
| Definitions | Clarify terminology | Define any terms that might be ambiguous or technical |
| Responsibilities | Who does what | Roles involved and their specific responsibilities |
| Procedure | The actual steps | Numbered, sequential steps with enough detail for execution |
| Safety/Warnings | Hazards and precautions | Any safety requirements, PPE, or critical warnings |
| References | Related documents | Links to related SOPs, policies, regulations, or forms |
| Revision History | Change tracking | Date, version, author, and description of each change |
| Approval | Sign-off | Approved by, date, next review date |
Not every SOP needs every section. A simple office procedure doesn't need a safety section. But regulated industries (healthcare, manufacturing, food production) typically require all sections.
Writing Style for SOPs
SOP writing follows specific conventions that differ from other business writing:
Use Imperative Mood (Commands)
SOPs tell people what to do. Write in the imperative mood — direct commands.
| Don't Write | Write |
|---|---|
| "The operator should check the temperature" | "Check the temperature" |
| "It is recommended that the sample be labelled" | "Label the sample" |
| "The form needs to be completed" | "Complete the form" |
Be Specific and Unambiguous
Vague instructions create inconsistency. Every step should have one clear interpretation.
| Vague | Specific |
|---|---|
| "Heat the solution" | "Heat the solution to 72°C ± 2°C" |
| "Wait for it to dry" | "Allow to air-dry for 15 minutes at room temperature" |
| "Add a small amount" | "Add 5ml using the calibrated pipette" |
| "Check regularly" | "Inspect every 4 hours during the production run" |
| "Contact the manager" | "Contact the Shift Manager on extension 4401" |
One Action Per Step
Each numbered step should contain one action. If a step contains "and," it's probably two steps.
Too many actions in one step:
"3. Collect the sample, label it with the batch number and date, place it in the refrigerated storage unit, and log the collection in the tracking system."
One action per step:
3. Collect the sample from the production line 4. Label the sample container with the batch number and collection date 5. Place the labelled sample in Refrigerated Storage Unit B (2-8°C) 6. Log the collection in the Sample Tracking System (form ST-001)
Include Decision Points Clearly
When a step involves a decision, make the conditions and outcomes explicit:
- Measure the pH level of the solution
- If pH is between 6.8 and 7.2: proceed to Step 9
- If pH is below 6.8: add 0.1M NaOH in 1ml increments until pH reaches 6.8-7.2, then proceed to Step 9
- If pH is above 7.2: add 0.1M HCl in 1ml increments until pH reaches 6.8-7.2, then proceed to Step 9
Include Warnings Before the Step, Not After
Safety warnings and critical notes must appear BEFORE the step they relate to, not after. A reader who performs the step before seeing the warning has already been exposed to the risk.
Wrong (warning after):
"8. Pour the acid into the beaker. ⚠️ Warning: Always add acid to water, never water to acid."
Correct (warning before):
"⚠️ Warning: Always add acid to water, never water to acid. 8. Slowly pour the acid into the beaker of water."
Common SOP Mistakes
Mistake 1: Written by Experts, for Experts
The person who knows the process best writes the SOP. But they unconsciously skip steps that are "obvious" to them. The test: give the SOP to someone who has never performed the task. If they can't follow it without asking questions, it's not complete.
Mistake 2: Too Much Detail vs Too Little
Over-detailed SOPs are as problematic as under-detailed ones. Nobody reads a 30-page SOP for a 10-minute task.
Right level of detail: Enough for a trained person in the role to perform the task correctly and consistently. You don't need to explain how to use a computer, but you do need to specify which system to use and what to enter.
Mistake 3: No Version Control
SOPs without version numbers, revision dates, or change histories become unreliable. Is this the current version? When was it last updated? Who approved it? Without version control, people may follow outdated procedures.
Mistake 4: Missing Definitions
Technical terms, abbreviations, and jargon need definitions — even terms that seem obvious. "Acceptable temperature" means nothing without a number. "Senior staff" means nothing without a title or role definition.
Mistake 5: No Review Schedule
SOPs go stale. Processes change, regulations update, systems upgrade. Every SOP needs a mandatory review date (annually at minimum, quarterly for high-risk procedures). Without it, SOPs drift from reality.
Mistake 6: Passive Voice Hides Responsibility
"The report should be reviewed" — by whom? Passive voice obscures who is responsible.
| Passive (unclear) | Active (clear) |
|---|---|
| "The sample should be tested" | "The Lab Technician tests the sample" |
| "Approval must be obtained" | "The Department Manager approves the request" |
| "The form is to be submitted" | "Submit the form to the Compliance Officer" |
SOP Templates by Industry
Healthcare/Clinical SOP Template
| Section | Content |
|---|---|
| Purpose | Clinical procedure being documented |
| Scope | Which patients/conditions/settings |
| Definitions | Clinical terminology, abbreviations |
| Responsibilities | Clinician roles (RN, MD, Allied Health) |
| Equipment | Required equipment with specifications |
| Procedure | Step-by-step clinical procedure |
| Safety | Infection control, PPE, contraindications |
| Documentation | What to record in patient charts |
| References | Clinical guidelines, regulatory standards |
Manufacturing/Production SOP Template
| Section | Content |
|---|---|
| Purpose | Production process being documented |
| Scope | Product lines, equipment, shifts |
| Definitions | Technical terms, quality specifications |
| Responsibilities | Operator, Supervisor, QA roles |
| Equipment | Machinery, calibration requirements |
| Materials | Raw materials, specifications, suppliers |
| Procedure | Step-by-step production process |
| Quality Checks | In-process inspection points, tolerances |
| Safety | Hazards, PPE, emergency procedures |
| Records | Batch records, quality logs |
Office/Administrative SOP Template
| Section | Content |
|---|---|
| Purpose | Business process being documented |
| Scope | Departments, roles, situations |
| Definitions | Business terms, system names |
| Responsibilities | Roles and approval authorities |
| Procedure | Step-by-step process |
| Systems | Software, access requirements |
| Exceptions | How to handle non-standard situations |
| Records | Filing, retention requirements |
Reviewing SOPs Before Approval
Before an SOP enters production, it should be reviewed against specific criteria:
SOP Review Checklist
| Criterion | What to Check |
|---|---|
| Completeness | All mandatory sections present? No missing steps in the procedure? |
| Clarity | Every step has one clear interpretation? No ambiguous language? |
| Accuracy | Steps match the actual current process? System names correct? |
| Specificity | Measurements, temperatures, times, and quantities are exact? |
| Action verbs | Steps use imperative mood? One action per step? |
| Safety | Warnings placed BEFORE the relevant step? All hazards addressed? |
| Responsibility | Every action has a named role? No passive voice hiding accountability? |
| Definitions | All technical terms defined? Abbreviations spelled out on first use? |
| Version control | Version number, date, author, and approval fields present? |
| Review date | Next review date specified? |
| Testability | Could a new person follow this SOP without asking questions? |
Using AI Review for SOPs
Configure an AI reviewer with SOP-specific criteria:
| Criterion | Weight | What It Checks |
|---|---|---|
| Step completeness | 3 | No missing steps, logical sequence, no gaps |
| Action verb usage | 2 | Imperative mood, one action per step |
| Specificity | 3 | Exact measurements, no vague terms like "regularly" or "approximately" |
| Safety placement | 2 | Warnings before the step, not after |
| Responsibility clarity | 2 | Named roles for every action, no passive voice |
| Definitions present | 1 | Technical terms defined, abbreviations spelled out |
Upload your organisation's SOP template and style guide as a knowledge base so the reviewer checks against your specific standards.
The review process: draft → AI review for completeness and clarity → subject matter expert review for accuracy → walk-through test with a non-expert → approval → publish with version number and review date.
Frequently Asked Questions
How long should an SOP be?
As long as it needs to be to completely describe the procedure, and not one word longer. A simple procedure might be one page. A complex manufacturing process might be 10-15 pages. If an SOP exceeds 15 pages, consider splitting it into multiple SOPs for sub-processes.
How often should SOPs be reviewed?
At minimum, annually. High-risk procedures (clinical, safety-critical, regulated) should be reviewed quarterly or after any incident. SOPs should also be reviewed whenever the process changes, equipment is upgraded, or regulations update.
Who should write the SOP?
The person who performs the process (or their supervisor) should draft the SOP. A technical writer or quality manager should then review for clarity and completeness. The subject matter expert knows the process; the reviewer ensures the document communicates it clearly.
What's the difference between an SOP, a policy, and a work instruction?
- Policy: What to do and why (high-level principles)
- SOP: How to do it (step-by-step procedure)
- Work instruction: Detailed instructions for a specific task within an SOP
A policy says "All equipment must be calibrated." An SOP describes the calibration procedure. A work instruction details how to calibrate a specific piece of equipment.
Should SOPs include screenshots?
Yes, when they involve software systems. Screenshots reduce ambiguity by showing exactly what the user should see at each step. Number screenshots to match step numbers. Update screenshots when systems change — outdated screenshots are worse than no screenshots.
How do I get people to actually follow SOPs?
Involve the people who perform the process in writing the SOP. Train on new SOPs before implementation. Make SOPs accessible (not buried in a shared drive). Keep them current — nothing undermines SOP compliance faster than an SOP that doesn't match reality.
Key Takeaways
- An SOP should be followable by someone who has never performed the task — if they need to ask questions, the SOP isn't complete.
- Use imperative mood, one action per step, and specific measurements — no vague language.
- Choose the right format: simple step list for linear procedures, hierarchical for sub-steps, flowcharts for decision points.
- Place safety warnings BEFORE the step, not after.
- Include all essential sections: purpose, scope, definitions, responsibilities, procedure, references, version control, and review date.
- Review before approval — check for completeness, clarity, specificity, and action verb usage.
- Set a mandatory review date — SOPs that aren't reviewed become outdated and dangerous.
This article is for informational purposes. SOP requirements vary by industry, regulation, and organisation. Always follow your industry's specific regulatory requirements and your organisation's quality management system.