The Ancillary Supplies and Services SIN, identified as SIN ANCILLARY under the GSA Multiple Award Schedule (MAS), covers supporting supplies and services that are not within the scope of another SIN but are needed to complement a contractor’s offering and provide a complete solution to a customer requirement. Unlike Order-Level Materials (OLMs), items offered under the ANCILLARY SIN are defined and priced at the MAS contract level rather than identified for the first time after an individual order requirement is known.
This distinction makes the ANCILLARY SIN useful when a contractor routinely provides supporting items as part of its federal solutions and can identify those items before an order is issued. Once awarded, the ancillary supplies or services become Schedule contract items, with pricing evaluated as part of the MAS contract rather than left entirely to the ordering activity to establish at the order level.
What the ANCILLARY SIN Covers
GSA places SIN ANCILLARY within the Miscellaneous category under Complementary Special Item Numbers. Its purpose is to accommodate supporting supplies and services that do not fit within another MAS SIN but are necessary to complement the contractor’s offering.
The key concept is support. The SIN is not intended simply as a way to place unrelated products or services on a Schedule contract. The proposed items should have a logical relationship to the solutions the contractor provides to government customers.
Depending on the contractor’s awarded scope and GSA’s approval, ancillary items can involve supporting products or services such as:
- project-specific supplies that complement an awarded solution;
- reproduction or document-production support;
- specialized supporting equipment;
- supporting services that do not fall within another applicable SIN;
- other identifiable supplies needed as part of a complete customer solution.
These are examples of how ancillary requirements can function, not a universal list of products automatically eligible for the SIN. A contractor seeking to add an item still needs to demonstrate that it falls within the applicable SIN scope and satisfy current MAS solicitation requirements.
GSA’s current SIN description also states that ANCILLARY may be used for orders and Blanket Purchase Agreements involving work or a project solely associated with the supplies or services purchased under the Schedule. This language is important because it means the SIN is not limited to situations where every order must contain another primary SIN.
At the same time, ANCILLARY should not be used to duplicate products or services that properly belong under another MAS SIN. The purpose is to fill a supporting gap within an awarded solution, not to replace more specific SINs that already cover the item being offered.
Why Contract-Level Identification Matters
One of the defining characteristics of the ANCILLARY SIN is timing. The contractor knows what the supporting supply or service is when it is added to the MAS contract. The item can therefore be defined, evaluated, priced, and awarded before an agency places a particular task or delivery order.
For example, suppose a contractor routinely provides a specialized supporting item with its primary solutions. If the contractor can describe that item and establish its pricing when adding it to the MAS contract, ANCILLARY may provide an appropriate contractual mechanism when the item is within the SIN’s scope.
This contract-level treatment has several consequences:
- The ancillary item is awarded under the contractor’s MAS contract.
- Its price is evaluated in connection with the Schedule contract.
- The item can appear as an awarded Schedule offering rather than an unidentified future order expense.
- The contractor does not need to rely on the OLM procedure merely because the item supports another solution.
- Ordering agencies can identify the item as part of the contractor’s awarded Schedule scope.
GSA specifically distinguishes ancillary items from OLMs on this basis. According to GSA’s OLM guidance, ancillary supplies and services that are known and can be awarded at the MAS contract level should be handled through the appropriate contract-level mechanism, while OLMs address supporting items that are unknown before the individual order or BPA requirement arises.
This makes advance planning important for Schedule contractors. A company that repeatedly encounters the same supporting expense across federal projects should determine whether that supply or service can be defined and appropriately added to its MAS contract rather than treating it as an unforeseen order-level requirement every time.
Contract-level identification does not mean that every customer will purchase the ancillary item or that it must appear in every order. It means the item has already been incorporated into the contractor’s Schedule scope and can be offered when appropriate to the customer’s requirement.
ANCILLARY vs. OLM vs. Open-Market Items
The ANCILLARY SIN is most easily misunderstood when it is confused with the Order-Level Materials SIN or open-market purchasing authority. All three mechanisms can help agencies obtain supporting elements of a broader Schedule solution, but they operate differently.
| Feature | ANCILLARY SIN | OLM SIN | Open-Market Item |
|---|---|---|---|
| MAS SIN | Yes | Yes | No |
| Schedule contract item | Yes | Yes | No |
| Item known at MAS contract award | Yes | No, identified at order or BPA level | Not part of the contractor’s Schedule |
| Price determination | MAS contracting officer at contract level | Ordering contracting officer at order level | Ordering contracting officer |
| Permitted order types | FFP, T&M, LH | T&M and LH CLINs | Depends on applicable acquisition |
| Primary authority | MAS contract and applicable ordering procedures | Special OLM ordering procedures | FAR 8.402(f) |
GSA’s comparison of Schedule support items confirms that ANCILLARY is a designated Schedule SIN and that its items are Schedule contract items. The MAS contracting officer performs the relevant price evaluation, while OLM pricing is established by the ordering activity. ANCILLARY can also be used with firm-fixed-price, time-and-materials, and labor-hour order structures, whereas OLMs are limited to T&M and LH CLINs.
OLMs address a different problem. They are supplies or services acquired in direct support of an individual Schedule order or BPA when those requirements were not known at the time of the Schedule contract award. The ordering contracting officer defines and prices them at the order level.
OLMs are also subject to specific restrictions. They may only be used in direct support of another awarded SIN, and the cumulative value of OLMs generally cannot exceed 33.33% of the total value of the order or BPA. These OLM-specific limitations should not be incorrectly applied to items already awarded under SIN ANCILLARY.
Open-market items are different from both. They are not Schedule contract items and may be added to a Schedule order only under the procedures applicable to open-market items, including FAR 8.402(f). The fact that a contractor can commercially supply an item does not make that item part of its MAS contract.
A contractor can hold both ANCILLARY and OLM authority on the same MAS contract when applicable. The important issue is selecting the mechanism that corresponds to when the requirement can be identified and how it is incorporated into the contract or order.
Adding Ancillary Supplies and Services to a MAS Contract
A contractor cannot simply label a new expense “ancillary” when responding to an RFQ and assume it has become part of the company’s Schedule contract. Items offered through SIN ANCILLARY need to be within the contractor’s awarded MAS scope.
For existing Schedule contractors, adding new ancillary offerings can therefore involve a contract modification. The contractor needs to follow the applicable MAS solicitation and modification requirements in effect when the request is submitted.
The contractor should be able to explain:
- what supply or service is being offered;
- how it supports the contractor’s broader federal solution;
- why another SIN does not more appropriately cover it;
- how the offering will be priced;
- what commercial or other supporting information is required by the solicitation;
- how the ancillary item relates to the contractor’s existing Schedule capabilities.
The distinction between ANCILLARY and a more specific SIN is especially important during this process. If GSA already provides a SIN specifically covering the product or service, the contractor should evaluate that SIN first rather than using ANCILLARY as a general-purpose alternative.
Pricing is another important difference from OLMs. Since ancillary items are identified at the Schedule contract level, they can be evaluated and awarded by the MAS contracting officer before an agency order is placed. GSA’s support-item comparison specifically assigns the price evaluation and fair-and-reasonable determination for ANCILLARY to the MAS contracting officer.
Contractors should consequently think about ANCILLARY as part of catalog and contract management. If an ancillary offering changes, is discontinued, or needs a pricing adjustment, the contractor may need to address that change through the appropriate Schedule contract administration process rather than simply altering an individual customer invoice.
How Agencies Use the ANCILLARY SIN
From an ordering agency’s perspective, SIN ANCILLARY can make it easier to acquire a complete solution through the MAS program when necessary supporting elements do not fit another SIN. Because the ancillary offering has already been awarded at the Schedule level, the agency is not dealing with the item in the same manner as an open-market product.
Consider an acquisition in which an agency needs a primary professional or technical solution plus supporting supplies that the contractor routinely provides. If those supporting supplies are already awarded under the contractor’s ANCILLARY SIN, the contractor can include them in its Schedule quote when consistent with the RFQ and applicable ordering procedures.
This structure can reduce the need to separate predictable supporting requirements from the rest of the Schedule solution. It also creates a clearer contractual distinction between items that are already part of the MAS contract and requirements that emerge only after an individual order has been defined.
Ordering activities still need to follow the applicable MAS ordering procedures. The existence of SIN ANCILLARY on a contractor’s Schedule does not eliminate competition requirements, scope considerations, evaluation criteria, or other rules governing Schedule orders.
Agencies and contractors should also verify the exact SINs awarded to the contractor. A company may hold several primary SINs without holding ANCILLARY, and an item available from the contractor commercially is not necessarily available from that contractor through MAS.
GSA also states that when SIN ANCILLARY is used in conjunction with a SIN eligible for Cooperative Purchasing, ANCILLARY is Cooperative Purchasing eligible. This can be relevant in acquisitions involving eligible state, local, tribal, and territorial government buyers using the Cooperative Purchasing Program.
When ANCILLARY Is the Appropriate MAS Mechanism
The most useful way to determine whether SIN ANCILLARY fits a requirement is to ask when the supporting item became identifiable and whether it can be established at the Schedule contract level.
ANCILLARY is generally relevant when the contractor can identify and price a recurring supporting supply or service in advance and the item complements its Schedule solutions without falling within another SIN. OLM is designed for a different situation, where the supporting requirement is unknown at MAS contract award and becomes identifiable only at the order or BPA level. Open-market procedures address items that are not Schedule contract items.
This distinction prevents ANCILLARY from becoming a catch-all category. A contractor should not use the SIN merely because an item is difficult to classify or because a customer asks for something outside the company’s existing Schedule scope. The contractor first needs to determine whether the requirement belongs under another SIN, qualifies for ANCILLARY, should be handled as an OLM when the applicable conditions are satisfied, or remains an open-market item.
For companies managing a GSA Schedule, reviewing recurring support requirements can reveal opportunities to improve contract coverage. If the same identifiable ancillary supplies or services repeatedly appear in customer solutions, adding them properly at the contract level may provide a more predictable mechanism for future Schedule orders.
The central distinction is straightforward: SIN ANCILLARY covers supporting supplies and services that can be identified, priced, and awarded at the MAS contract level. OLM procedures address supporting requirements that cannot be identified until the order level. Keeping that boundary clear helps contractors structure compliant MAS offerings and helps ordering agencies understand which components of a proposed solution are already within the contractor’s Schedule contract.
