These positions are scarce by design, not by budget. OPM controls how many each agency may have, and the allocation process runs on a biennial cycle tied to SES allocations. If you are interested in this track, the useful conversation is with your agency's executive resources office about whether an allocation exists — not with USAJOBS.
I What ST and SL actually are
When FEPCA abolished grades GS-16, GS-17 and GS-18, the employees in them moved into alternative pay systems — including the SL/ST system established under 5 U.S.C. 5376, effective with the first pay period on or after 23 April 1991.
What survives is a track for people whose work is classified above GS-15 but is not executive. They carry the pay plan codes SL and ST, are paid under section 5376, and are governed by 5 CFR part 534 subpart E and 5 CFR part 319.
II The line between them
| SL — Senior Level | ST — Scientific or Professional | |
|---|---|---|
| Authority | 5 U.S.C. 5108 allocation | 5 U.S.C. 3104 allocation |
| Test | Classified above GS-15 and does not meet SES functional criteria | Engaged in research and development |
| Fields | Any senior non-executive work | Physical, biological, medical or engineering sciences, or a closely related field |
| Typical holder | Senior attorney, economist, policy expert | Research scientist, senior engineer |
| Paid under | 5 U.S.C. 5376 — identical range | |
Within an agency subject to the SES, a position classified above GS-15 that meets one or more of the SES functional criteria at 5 U.S.C. 3132(a)(2) must be placed in the SES — and 5 U.S.C. 3104 states plainly that the ST authority does not apply to an SES position. Under 5 CFR 319.203(b) an ST allocation may only be used for a position properly classified above GS-15 against published classification standards. An agency cannot route an executive job through ST to skip the Qualifications Review Board.
III The pay range
Section 5376 requires a rate not less than 120 percent of the minimum rate for GS-15, with the head of the agency fixing the actual rate within the range under OPM regulations.
| 2026 SL/ST range | Minimum | Maximum |
|---|---|---|
| Certified appraisal system | $151,661 | $228,000 (EX-II) |
| Not certified | $151,661 | $209,600 (EX-III) |
No grades, no steps, and no scheduled increases — the same structure as the executive band described in the Senior Executive Service. Movement within the range is performance-based and discretionary.
The Senior Professional Performance Act of 2008, Public Law 110-372, amended section 5376 so that an agency attaining certification of a performance appraisal system covering senior professionals may fix rates up to Executive Schedule Level II. OPM grants certification with OMB concurrence, and only where the system makes meaningful distinctions based on relative performance. Certification is therefore worth $18,400 of ceiling to an ST or SL employee exactly as it is to an executive.
IV Against the SES, side by side
| SES | ST / SL | |
|---|---|---|
| 2026 range | $151,661–$228,000 | Identical |
| Locality pay | None | None |
| ECQs | All five required | None |
| QRB certification | Mandatory, cannot be waived | Not applicable |
| Performance awards | 5–20% of basic pay | Agency award programmes |
| Presidential Rank Awards | Eligible | Eligible |
| Aggregate cap | $292,300 / $253,100 | Same |
| Reassignment authority | Broad, within the agency | Position-based |
| Requires managing people | Yes | No |
| Path to agency leadership | Yes | No — terminal technical track |
Read that table twice if you are a GS-15 technical specialist weighing the executive track. The compensation columns are identical. The qualification columns are not, and neither is the job.
Where the three tracks sit, in 2026 dollars
GS-15 pay varies by locality and is capped at EX-IV. SES and SL/ST share one nationwide band with no locality adjustment at all.
V Why they are so scarce
Because OPM rations them individually, and an agency cannot create one on its own.
- Under 5 U.S.C. 3104, OPM determines the maximum number of ST positions an agency may establish, and may revise that number over time.
- Under 5 U.S.C. 5108(a), OPM authorizes the maximum number of positions that may be classified above GS-15 — the SL allocation.
- Requests are normally considered during the biennial allocation process established for SES positions under 5 U.S.C. 3133, or ad hoc between cycles as out-of-cycle requests.
These positions rarely appear on USAJOBS, and when they do it is often after an agency has already identified the person it wants the allocation for. The productive move is not to watch announcements but to ask your agency's executive resources office two questions: does the agency hold any unused ST or SL allocations, and when is the next allocation cycle. Scarcity here is administrative, not competitive — which means it rewards people who understand the process rather than people who apply fastest.
VI Awards and the aggregate cap
Senior professionals sit inside the same award and cap machinery as executives.
Presidential Rank Awards are available to SL and ST employees alongside SES members — 35 percent of basic pay for a Distinguished award, 20 percent for Meritorious, each paid as a lump sum.
The aggregate limitation on pay under 5 U.S.C. 5307 applies identically. Agencies with certified appraisal systems covering senior professionals may apply the higher limitation equivalent to the Vice President's salary, $292,300 in 2026; those without certification are held to Executive Schedule Level I, $253,100. Anything above the cap is deferred to the following January rather than lost, and then counts against that year's ceiling. The mechanics are worked through in SES pay and performance.
VII Who this track actually suits
The honest test is not about money, because the money is the same. It is about what you want your days to contain.
Two GS-15s, same salary, different answer
Both are GS-15 step 8 research engineers. Both are eligible to compete for the SES.
The other is the person the agency calls when the hardest technical problem lands. Pushed into the SES, she would spend her time on budget, staffing and stakeholder management — and the agency would lose the capability it promoted her for. An ST position pays her the same and keeps her doing the work.
The government designed this track precisely so that technical excellence would not have to be converted into management to be paid properly. It works — when people know it exists.
VIII The playbook
| Situation | What to do |
|---|---|
| GS-15 technical specialist | Price ST and SL before assuming the SES is the only way up. Same range. |
| Interested in the track | Ask executive resources whether the agency holds unused allocations. |
| None available | Ask when the next biennial allocation cycle runs, and whether an out-of-cycle request is possible. |
| In research and development | ST is the authority. Confirm your work meets the R&D test in 5 U.S.C. 3104. |
| Senior but not research | SL is the authority — classified above GS-15, not meeting SES functional criteria. |
| Offered a position | Ask whether the agency's senior professional appraisal system is certified. Worth $18,400 of ceiling. |
| Negotiating the rate | No steps and no automatic increases. The entry number compounds through every future award. |
| Told ST avoids the QRB for an executive job | It cannot. A position meeting SES functional criteria must be in the SES. |
| Rank award year | Same aggregate cap as the SES. Model it before counting the money. |
| Weighing against the SES | The pay is identical. Decide on the job, not the salary. |
If this track fits you
- Confirm whether your work meets the ST research test or the SL above-GS-15 test.
- Ask your executive resources office about existing allocations.
- Find out when the next biennial allocation cycle runs.
- Confirm the agency's senior professional appraisal certification status.
- Price the range against your current locality-adjusted GS pay.
- Remember there is no locality adjustment on top of the SL/ST rate.
- Negotiate the entry rate — every future award is a percentage of it.
- Confirm your eligibility for Presidential Rank Awards in writing.
- Understand this is a terminal technical track, not a route to agency leadership.
- Decide on the work you want, since the compensation is the same either way.
Frequently asked questions
Both are senior positions classified above GS-15 and both are paid under 5 U.S.C. 5376, but they exist under different authorities. A Senior-Level position is one an agency has determined is classified above GS-15 under 5 U.S.C. 5108 and that does not meet the Senior Executive Service functional criteria. A Scientific or Professional position is established under 5 U.S.C. 3104 and must be engaged in research and development in the physical, biological, medical, or engineering sciences, or a closely related field. In short, ST is for research; SL is for senior non-executive work that is not research.
The same statutory range as the Senior Executive Service. In 2026 that is a minimum of $151,661, which is 120 percent of the rate for GS-15 step 1, and a maximum of $228,000 in agencies with a certified performance appraisal system covering senior professionals, or $209,600 without certification. The head of the agency fixes the rate within that range under regulations OPM prescribes, so there are no grades and no steps.
No. The Executive Core Qualifications and the Qualifications Review Board apply to initial career appointments to the Senior Executive Service. ST and SL positions carry neither. What they require instead is demonstrated technical or professional standing at a level that justifies classification above GS-15, which for an ST position means genuine research and development expertise. For a technical specialist, that is a materially different and often more attainable bar than proving Leading People and Building Coalitions.
Because they are individually rationed. OPM determines the maximum number of ST positions an agency may establish under 5 U.S.C. 3104, and authorizes SL allocations under 5 U.S.C. 5108. An agency cannot simply create one. Requests are normally considered during the biennial allocation process established for SES positions under 5 U.S.C. 3133, or on an ad hoc basis between cycles. The scarcity is structural rather than a matter of budget, which is why these positions rarely appear on USAJOBS and often go to people already known to the hiring organisation.
No, and the statute is explicit. Within an agency subject to the SES, a position classified above GS-15 that meets one or more of the SES functional criteria in 5 U.S.C. 3132(a)(2) must be placed in the SES, and 5 U.S.C. 3104 provides that the ST authority does not apply to an SES position. Under 5 CFR 319.203(b) an ST allocation may only be used for a position the agency has determined is properly classified above GS-15 consistent with published classification standards. Agencies cannot route an executive job through the ST authority to avoid the QRB.
Yes. Senior professionals are eligible for Presidential Rank Awards alongside SES members, at 35 percent of basic pay for a Distinguished award and 20 percent for Meritorious. They are also covered by the same aggregate limitation on pay under 5 U.S.C. 5307: agencies with certified performance appraisal systems covering senior professionals may apply the higher limitation equivalent to the Vice President's salary, and those without certification are limited to Executive Schedule Level I.
The 2008 Act, Public Law 110-372, amended 5 U.S.C. 5376 to promote performance-based pay by letting an agency that attains certification of a performance appraisal system covering senior professionals fix rates of basic pay for those employees up to Executive Schedule Level II. Before it, the senior professional ceiling was lower. The practical consequence today is that certification status determines your ceiling in exactly the same way it does for the SES, and it is worth asking about before you accept a position.
If your value to the government is technical depth rather than organisational leadership, usually yes. You get the same pay range, the same award eligibility, and the same aggregate cap, without ECQs, without a QRB, and without the executive reassignment authority that comes with a career SES appointment. What you give up is the executive career ladder itself: ST and SL are terminal technical positions rather than steps toward agency leadership. The honest question is whether you want to lead an organisation or be the person it relies on.