Scalable Third-Party Risk Management for SaaS Companies

A vendor program scales when the depth of each review follows the harm a vendor could cause. That harm depends on the data the vendor holds, its access to your systems, and its role in your service. The goal of scalable third-party risk management is to spend effort where a vendor could hurt you most and keep low-risk tools cheap to manage.

The question comes up when an enterprise prospect sends a security questionnaire, a bank asks how you oversee subcontractors, or an EU customer wants a say before you add a subprocessor. When every vendor gets the same review, a stock-photo subscription takes as many hours as the database that stores your customer records.

This guide is for founders, CTOs, and security leads at SaaS companies without a third-party risk team that sell to enterprises, banks, or EU customers.

Key takeaways

• Proportional oversight lets a program scale: the 2023 interagency guidance of US banking regulators ties the level of oversight to the risk of each relationship, so review depth can follow risk.
• Tier vendors on data, access, and business impact: NIST's supply chain quick-start guide gives those three as example criteria for supplier criticality. The tier then sets the evidence you ask for, the contract terms, and how closely you monitor.
• Some customer rules reach your vendors through you: a bank customer's due diligence looks at how you oversee subcontractors, and GDPR Article 28 bars a processor from engaging another processor without the customer's prior written authorization.
• Automate the paperwork and keep the decisions with a named person: a tool can run intake and schedule reassessments, while a person confirms critical tiers and accepts residual risk.

What scalable third-party risk management means

A third-party risk program is scalable when the effort it spends on each vendor follows that vendor's risk, so a new low-risk tool adds little work and a new critical vendor gets a full review. Outside vendors and service providers bring the risks that third-party risk management assesses and reduces. The AICPA's SOC 2 criteria give these as examples of threats from vendor relationships:

• financial failure;
• security vulnerabilities;
• operational disruption;
• failure to meet business or regulatory requirements.

The 2023 Interagency Guidance on Third-Party Relationships of three federal banking agencies states the principle: "Not all relationships present the same level of risk, and therefore not all relationships require the same level or type of oversight or risk management." NIST SP 800-161r1 says the depth and maturity of a supply chain risk capability "should be based on" the organization's circumstances, including its compliance requirements and risk tolerance.

The guidance addresses banking organizations, and NIST says nongovernmental organizations may use SP 800-161r1 on a voluntary basis. For a SaaS company both are models to follow, and the bank guidance also describes the due diligence your bank customers run on you.

Why vendor risk gets harder as a SaaS company grows

A new vendor can add a path to your data, and each new enterprise customer adds a reviewer who asks about those paths. A third-party risk program reduces your exposure to breaches along those paths and helps you answer the reviewers. Four pressures grow with the vendor list:

• Breaches run through vendors: Verizon's 2026 Data Breach Investigations Report (DBIR) found that breaches with third-party involvement increased by 60% from the previous year's dataset, reaching 48% of total breaches. The 2026 dataset covers more than 22,000 confirmed breaches involving organizations in 145 countries.
• Enterprise customers review you before they sign: a security questionnaire from an enterprise prospect can stall a deal, as our startups page notes.
• Customers ask for audit evidence: bank customers can write into vendor contracts a right to audit you and the audit reports they will receive, such as SOC reports (step 5). The AICPA's proposed 2027 SOC 2 criteria, still exposure drafts and not in force, name today's "third-party risk landscape" as a reason for the update.
• Customer rules reach your own vendors: bank and EU customers have rules on the subcontractors and subprocessors you use, covered in the next chapter.

What auditors and enterprise customers expect from your vendor program

Auditors and enterprise reviewers work from frameworks that describe vendors being inventoried, ranked by risk, and monitored over time. In third-party risk management, SaaS companies are both the customer and the third party. You assess your vendors, and your customers assess how you do it.

SOC 2 reports and ISO 27001 certification: the evidence customers ask for

A SOC 2 report covers your vendor program under criterion CC9.2: "The entity assesses and manages risks associated with vendors and business partners." Its points of focus, which the AICPA says may not all apply to every entity, highlight these practices:

• Requirements: the entity sets each engagement's scope of services, roles, and service levels.
• Tiers: the entity "inventories, tiers, and assesses, on a periodic basis" threats from its vendors and from the vendors they rely on.
• Follow-through: accountability is assigned, performance is assessed as often as a vendor's risk warrants, and exit procedures may include the safe return and removal of data.

ISO 27001 certification is another kind of evidence a customer may accept, and NIST's supply chain quick-start guide lists certifications among the evidence a supplier can be asked to provide. The standard has its own supplier controls in Annex A, among them 5.19 to 5.21, and mappings in NIST's catalog of informative references link them to the CSF 2.0 supply chain outcomes below. We recommend one vendor program for SOC 2 and ISO 27001 together, so one inventory and one set of reviews serve both.

NIST CSF 2.0: the supply chain outcomes (GV.SC)

NIST CSF 2.0, published on February 26, 2024, lists these supply chain outcomes under its Govern function:

• Roles (GV.SC-02): supplier and partner responsibilities are set and communicated.
• Priority (GV.SC-04): "Suppliers are known and prioritized by criticality."
• Contracts (GV.SC-05): requirements are integrated into supplier agreements.
• Due diligence (GV.SC-06): supplier checks happen before a relationship starts.
• Monitoring (GV.SC-07): supplier risks are "monitored over the course of the relationship."
• Incidents (GV.SC-08): relevant suppliers join incident response and recovery.
• Exit (GV.SC-10): plans cover activities after an agreement ends.

Your customers' rules: banks, other financial institutions, EU customers, and public companies

These customers bring their own rules:

• Banks: under the interagency guidance, final as of June 6, 2023, a bank's due diligence typically includes "how the third party selects and oversees its subcontractors." On September 11, 2026, the three agencies and the National Credit Union Administration requested comment on replacement guidance, and the three banking agencies plan to rescind the existing guidance once the replacement is final.
• Other financial institutions: the FTC's Safeguards Rule requires covered financial institutions to assess service providers periodically "based on the risk they present."
• EU customers: when the customer is the controller and you are its processor, GDPR Article 28 says you "shall not engage another processor without prior specific or general written authorisation of the controller." In practice, a new vendor that will process that customer's personal data on your behalf needs the customer's authorization first, given by name or in advance. Under a general authorization, you must announce changes so the customer can object.
• Public-company customers: SEC Regulation S-K Item 106 asks a registrant to describe its processes, if any, for overseeing cybersecurity risks from "its use of any third-party service provider," which can include you.

A trust center is a public page with your security posture, a current subprocessor list, and sensitive documents available on request. It shows all four customer types in one place how you meet those rules, so fewer questionnaires need answers written from scratch.

How to build a third-party risk program that scales

Build your third-party risk program in seven steps and size each one to the vendor tiers you set in step 3. The steps follow the life cycle the interagency guidance describes, which has five phases:

• planning;
• due diligence and third-party selection;
• contract negotiation;
• ongoing monitoring;
• termination.

Steps 1 to 4 cover planning and due diligence, step 5 contracting and exit, and steps 6 and 7 monitoring. For a walk-through of setting up a program inside a compliance platform, see our vendor risk management guide.

1. Name one owner and write a one-page policy

Make one role accountable for vendor risk. NIST's quick-start guide for supply chain risk management (SP 1305) says to "Identify one or more specific roles or positions that will be responsible and accountable" for that work, and suggests a RACI chart to record who else takes part. At a SaaS company the owner can be the head of security or the CTO.

Keep the policy to one page that says how a vendor gets its tier, what evidence each tier provides, and who may accept a risk that stays open. You finish with a named owner and a policy a new hire can follow.

2. Build one vendor inventory

List every vendor in one place before you rank any of them. The interagency guidance ties "a complete inventory of its third-party relationships" to periodic risk assessments that show "whether risks have changed over time," and SP 1305 says to "Keep a record of all suppliers, prioritized based on the criticality criteria."

Vendors are bought in different ways, so pull the list from each of these places:

• signed contracts and order forms;
• card and accounts-payable spend;
• the app list in your single sign-on (SSO) provider;
• the subprocessor list you publish for customers.

Record each vendor's internal owner, the data it handles, the access it has, and its renewal date. That one list is what step 3 ranks.

3. Tier vendors by data, access, and business impact

Assign each vendor a tier, with a written reason, using the three example criteria NIST's quick-start guide gives for supplier criticality:

• Data: the sensitivity of the data the vendor processes or stores. For example, a database host holding customer records ranks above a tool that never sees them.
• Access: the vendor's degree of access to your systems. For example, admin rights in production rank above read-only access to marketing data.
• Business impact: how much your product depends on the vendor's service. For example, a vendor whose outage stops your service belongs near the top.

We use these criteria to capture the operational, compliance, and strategic risks the interagency guidance names. To decide which vendors are Tier 1, borrow two characteristics the guidance gives for critical activities and treat a relationship as critical if it could cause significant risk when the vendor fails to meet expectations, or if it has significant customer impacts. Record the tier on each vendor's inventory entry; the guidance accepts a criticality level for each relationship or a list of critical activities.

Leave contract value out of the tier, since a free tool can hold more customer data than an expensive one. Table 1 is a starting matrix that sets out what each tier gets.

Table 1. A starting tier matrix for SaaS vendors

Sources: BD Emerson analysis based on the interagency guidance (sections B and C.2 to C.4) and NIST SP 1305 (Activities 2 and 3).

4. Set the review depth for each tier

Match the effort of each review to the tier and write the depth down. The interagency guidance says: "The scope and degree of due diligence should be commensurate with the level of risk and complexity of the third-party relationship." SP 1305 names four kinds of evidence a supplier may be asked to show, and we map them to the tiers:

• Self-attestation: answers to intake questions, enough for Tier 3.
• Conformance to known standards: the standard a Tier 2 vendor follows, with the documents behind it.
• Certifications: for a Tier 1 vendor, an ISO 27001 certification or a SOC 2 attestation report; either one is enough.
• Inspections: your own look at a Tier 1 vendor's controls where its reports leave gaps.

Run the review before you sign, as CSF outcome GV.SC-06 expects. Sizing each 3rd party vendor risk assessment to its tier keeps the deep reviews for vendors that hold your customers' data, and the due diligence checklist in our vendor risk management guide covers what to ask.

5. Write tier-based contract terms, including the exit

Write the protections you need into the contract before signature, scaled to the tier. For Tier 1 vendors, the contract can cover:

• Audit rights and reports: the interagency guidance notes that a contract "often establishes the banking organization's right to audit" and suggests stating which audit reports the customer receives, for example SOC reports.
• Subcontractor notice: when and how the vendor tells you it uses, or plans to use, a subcontractor.
• Data protection flow-down: under GDPR Article 28(4), the same data protection obligations you owe an EU customer are imposed on your subprocessor by contract, and you remain fully liable to the customer for its performance.
• Incident duties: the vendor's part in your incident planning, response, and recovery.
• Exit terms: what happens to your data and the vendor's access after the agreement ends.

Tier 2 vendors get a shorter set of security, confidentiality, and breach notice terms, and Tier 3 vendors sign standard terms.

6. Monitor by tier and reassess on triggers

Monitor Tier 1 vendors continuously where you can, reassess the rest on a schedule, and add a review when a trigger fires. The interagency guidance says monitoring "may be conducted on a periodic or continuous basis," with closer or more frequent monitoring for higher-risk relationships. Vendor gaps can stay open after onboarding. In the 2026 DBIR's look at third-party cloud exposures over time, only 23% of the third-party organizations fully remediated missing or improperly secured multi-factor authentication on their cloud accounts.

The guidance names signals that call for escalation:

• material or repeat audit findings;
• deterioration in financial condition;
• security breaches or data loss;
• service interruptions;
• compliance lapses.

Add a change in a vendor's own subprocessors to the list for vendors that handle EU personal data. Write the cadence and the trigger list into the policy from step 1.

If a Tier 1 vendor's SOC 2 audit period ended months ago, ask for a bridge letter that covers the months since.

7. Report to leadership and review the program

Send a one-page report to leadership and the board on a cadence you choose, and use it to review the program itself. In the bank model, the board "has ultimate responsibility for providing oversight for third-party risk management and holding management accountable." A SaaS board can play the same role by reviewing four measures we suggest:

• Coverage: the share of vendors in the inventory that have a tier.
• Tier mix: how many vendors sit in each tier.
• Overdue reviews: reassessments past their due date.
• Open findings: issues from reviews that are still unresolved, each with an owner and a date.

A company preparing to go public can use this report as the record behind its own Item 106 description of third-party oversight.

What changes as you grow from 20 to 200 vendors

The counts of 20 and 200 vendors are examples. As a SaaS company grows, the seven steps stay the same and get deeper. Each stage below starts with an event in the business:

• Early stage, about 20 vendors: the trigger is an enterprise security questionnaire, the same signal our guide to SOC 2 for startups names for starting a first SOC 2 report. Run steps 1 to 3 lightly: one owner, one list, and the Tier 1 vendors named.
• Growth stage, dozens of vendors: a SOC 2 report or ISO 27001 certification is in place, and bank or EU customers arrive. Write down steps 4 to 6 for each tier and start tracking subprocessor changes for EU customers.
• Scale-up, about 200 vendors: public-company customers or an IPO come into view. Automate collection and scheduling, report to leadership on a cadence, and keep a description of the process ready for a customer's or your own Item 106 disclosure.

Table 2 summarizes the three stages and the gap each one exposes if the program stays as it was.

Table 2. How the program changes by growth stage

Source: BD Emerson analysis.

What to automate first, and what to keep human

Automate the work that repeats on a schedule, and keep the decisions that accept risk with a person. The interagency guidance says a bank's use of third parties "does not remove the need for sound risk management." A tool that runs your vendor program is a third party too, so it does not take the risk decisions off your hands.

Automate these first:

• Intake: new vendors enter the inventory from procurement or SSO with an internal owner attached.
• Tiering questions: the data, access, and business-impact questions run at intake, so a draft tier exists before the review starts.
• Evidence requests and expiry tracking: the tool requests reports and documents and flags each one as its audit period ages.
• Reassessment scheduling: each tier's cadence becomes dated tasks for the owner.
• Escalations and reports: triggers reach the program owner, and the leadership measures are produced on schedule.
• Questionnaire and evidence review: AI can summarize a vendor's answers and reports for the reviewer, who still signs off on the result.

Keep these decisions with a named person:

• A critical tier: a tool can propose Tier 1, and the owner confirms it.
• Residual risk: an open finding stays open only with a person's sign-off and a review date.
• Contract exceptions: a missing audit right or exit term needs approval from someone accountable.
• Ending a critical relationship: leadership decides, with an exit plan, following the bank model, which holds the board and management accountable for third-party risk.

The tool can be a compliance platform you already use. We are a certified Vanta partner and work in other tools our clients choose.

Conclusion

The workload of third-party risk management for SaaS companies stays manageable when each vendor's tier decides how deep its review, contract terms, and monitoring go. Start with an owner and one inventory and give every vendor a tier. The work then grows with the number of critical vendors. The evidence auditors and customers ask for sits in your inventory, contracts, and leadership report.