GSA's flagship professional services vehicle — structure, eligibility, and what holding a seat actually means.
Last reviewed on May 12, 2026.
OASIS+ is the General Services Administration's multiple-award contract vehicle for professional services. It is the successor to the original OASIS and OASIS Small Business contracts. Like its predecessor, OASIS+ is structured as a family of indefinite delivery, indefinite quantity (IDIQ) contracts that federal agencies use to compete and award task orders for professional services work. Ordering agencies pay a small fee to GSA on each task order.
OASIS+ is among the largest federal professional services vehicles, with billions of dollars in projected task order volume across the contract's life. For firms that perform professional services work, holding an OASIS+ contract is a significant business development asset; for firms that do not hold one, partnering with a holder is often the path to OASIS+ task orders.
OASIS+ is divided into separate pools based on the contracting status of the holder. The pools share the same scope but have different eligibility, separate competition, and separate price evaluation:
A firm can hold contracts in multiple pools if it meets the eligibility for each. Holding an unrestricted contract and a small business pool contract simultaneously is common for firms growing through the size threshold.
OASIS+ scope covers a broad range of professional services organized into domains. The exact domains and definitions are set by GSA; broadly, they include:
The labor category structure under OASIS+ is broad enough to accommodate most professional services work. Firms qualify under one or more domains in their proposal.
Task order procedures under FAR 16.505 are faster than full open competitions. Most task order competitions close in weeks rather than months.
OASIS+ is harder to obtain than a GSA Schedule but offers narrower direct competition (only contract holders in your pool can bid task orders). Typical proposal requirements during the original solicitation:
GSA periodically opens on-ramp opportunities to add new contract holders to specific pools. On-ramps are competitive and use criteria similar to the original solicitation. Off-ramps remove non-performing contractors. Firms not on the initial award list watch on-ramp announcements closely.
OASIS+ task orders use a mix of contract types — firm-fixed-price, time-and-materials, labor-hour, cost-reimbursement, and hybrids. The master contract establishes ceiling rates per labor category at the contract level; task orders price within or below those ceilings based on the specific scope.
Pricing competitiveness on OASIS+ task orders depends heavily on the firm's indirect rate structure. Firms with lean indirects can underbid competitors at the same fully burdened rate, leaving more profit margin; firms with heavy overhead struggle to match. See DCAA compliance and accounting systems for the underlying discipline.
| Vehicle | Best for | Distinct features |
|---|---|---|
| OASIS+ | Complex professional services, multi-domain task orders | Pool-based competition, broad scope, strong agency adoption |
| GSA Schedule (MAS) | Commercial professional services, broad agency reach | Open to many holders; lower competitive intensity per task order is rare |
| CIO-SP4 | IT services with health-IT emphasis | NIH-administered; multiple task areas including emerging tech |
| Agency-specific BPAs | Single-agency mission support | Single buyer; strong incumbent dynamics |
Both, and they answer different questions. Pools are defined by the holder's contracting status — unrestricted, total small business, 8(a), WOSB, HUBZone, and SDVOSB — and determine who is eligible to compete for a given task order. Domains are scope areas within the professional services umbrella, such as management and advisory, technical and engineering, research and development, intelligence services, environmental, facilities and logistics, and financial management. You hold a contract in one or more pools, and you qualify within one or more domains.
By domain. SINs (Special Item Numbers) are a GSA Multiple Award Schedule construct, not an OASIS+ one — confusing the two is common because both are GSA programs. Under OASIS+, the ordering agency selects a pool and a domain, and the task order RFP goes to holders qualified in that combination. If your contract does not cover the domain, you are not in the competition regardless of your capability.
Yes. It is a family of government-wide indefinite delivery, indefinite quantity (IDIQ) contracts operated by GSA for professional services, and it is the successor to the original OASIS and OASIS Small Business contracts. Any federal agency can place task orders under it, paying GSA a small fee on each order.
Not through a small business pool. Size is evaluated against the NAICS code assigned to the individual task order, so a firm that is small under its contract's underlying code can still be ineligible for a specific order carrying a different code with a lower size standard. Firms that grow past the threshold typically hold an unrestricted contract alongside a small business pool contract for exactly this reason — see NAICS codes and size standards for how the code assignment works.
Holding the contract only makes you eligible; orders are won on the individual competitions. In practice the firms that win consistently do three things: they track the ordering agencies in their domain rather than waiting for RFPs to arrive, they build past performance citable at task order level rather than at contract level, and they staff a dedicated task order response capability, because order cycles are measured in weeks. A vehicle you cannot resource is a vehicle that produces no revenue.
You would need a contract in the unrestricted pool, which requires winning one through the award or on-ramp process — outgrowing a small business size standard does not convert your existing contract. This is why firms approaching the threshold commonly pursue an unrestricted award while they still hold their small business contract, rather than waiting until they no longer qualify.