Last Updated: September 6, 2026 Reading Time: 9 min

A Reddit thread this week claimed a single county line can change a federal salary by $39,391. Commenters piled on with their own county pairs, but nobody posted verified numbers. So we computed them. This is the locality pay county line cliff, pair by pair, using OPM's 2026 tables and the same formula that runs our GS Pay Calculator.

Why a County Line Controls Your Paycheck

Locality pay is not a cost-of-living adjustment tied to your ZIP code. It is a percentage OPM applies on top of your base GS rate, and it depends on one thing: which locality pay area contains your official duty station.

OPM defines each area as a list of counties (plus a handful of independent cities). If your duty station's county is on the list, you get that area's percentage. If it is not on any list, you get the Rest of U.S. rate, 17.06% in 2026.

The rule that trips people up is in 5 CFR 531.604: the rate follows your official worksite, not your residence. Live in a Rest of U.S. county and commute into a Washington-Baltimore office? You get 33.94%. Live inside the Washington-Baltimore area but work at an office in a Rest of U.S. county? You get 17.06%.

The Federal Salary Council redraws the lines through a documented process, not by feel. To add a single county to an adjacent locality area, that county needs 400 or more GS employees and a commuting "employment interchange rate" of at least 7.5% with the existing area. A multi-county area needs 1,500 employees at the same 7.5% threshold. Counties that miss the cutoff stay out, no matter how close the drive is.

For 2026, OPM stated that the geographic definitions are identical to 2025. No county was added, moved, or removed anywhere in the country.

The $39,391 Example, Reproduced

The viral number comes from the Sierra Nevada foothills. Calaveras County, CA sits inside the San Jose-San Francisco-Oakland locality at 46.34%, the highest rate in the nation. Tuolumne County, right next door and sharing the Stanislaus National Forest, is Rest of U.S. at 17.06%.

The math at GS-15 Step 3, base pay $134,810:

  • Calaveras side: $134,810 × 46.34% = $62,471 locality. Total $197,281, which exceeds the Executive Schedule Level IV cap, so pay is capped at $197,200.
  • Tuolumne side: $134,810 × 17.06% = $22,999 locality. Total $157,809, well under the cap.
  • Gap: $39,391.

Step 3 is the peak on purpose. At Steps 1 and 2, the Calaveras side has not hit the cap yet, so the gap is smaller ($37,005 and $38,239). From Step 4 onward, the Calaveras side sits frozen at $197,200 while the Tuolumne side keeps climbing with each step, so the gap shrinks every year until it bottoms out at $4,869 at Step 10.

One correction to the thread: a commenter called this a "25% difference." The real spread is 29.28 percentage points (46.34 minus 17.06). Directionally right, numerically low.

14 Adjacent-County Pairs, Computed

Every pair below is two counties that share a border and sit in different locality areas. County membership comes from OPM's official 2026 locality area definitions. Dollar figures use the 2026 GS base table and the calculation our GS Pay Calculator runs: base × locality percentage, rounded to the dollar, then capped at $197,200.

FedTools 2026 analysis of OPM locality area definitions and the 2026 GS pay table.

# Higher-rate county (area, %) Lower-rate county (area, %) Spread (pts) GS-7/1 gap GS-11/1 gap GS-13/5 gap GS-15/10 gap
1 Calaveras, CA (San Jose-SF-Oakland, 46.34%) Tuolumne, CA (Rest of U.S., 17.06%) 29.28 $12,621 $18,680 $30,173 $4,869
2 Sullivan, NY (New York-Newark, 37.95%) Delaware, NY (Rest of U.S., 17.06%) 20.89 $9,005 $13,327 $21,527 $4,869
3 San Bernardino, CA (Los Angeles, 36.47%) Inyo, CA (Rest of U.S., 17.06%) 19.41 $8,367 $12,383 $20,002 $4,869
4 Kern, CA (Los Angeles, 36.47%) Tulare, CA (Fresno, 17.65%) 18.82 $8,113 $12,006 $19,394 $3,900
5 Madison, TX (Houston-The Woodlands, 35.00%) Leon, TX (Rest of U.S., 17.06%) 17.94 $7,733 $11,445 $18,487 $4,869
6 Orange, VA (Washington-Baltimore, 33.94%) Albemarle, VA (Rest of U.S., 17.06%) 16.88 $7,276 $10,769 $17,395 $4,869
7 Cumberland, ME (Boston-Worcester-Providence, 32.58%) Oxford, ME (Rest of U.S., 17.06%) 15.52 $6,690 $9,901 $15,993 $4,869
8 Windham, CT (Boston-Worcester-Providence, 32.58%) Tolland, CT (Rest of U.S., 17.06%) 15.52 $6,690 $9,901 $15,993 $4,869
9 York, PA (Washington-Baltimore, 33.94%) Cumberland, PA (Harrisburg-Lebanon, 19.43%) 14.51 $6,255 $9,257 $14,953 $975
10 Adams, PA (Washington-Baltimore, 33.94%) Cumberland, PA (Harrisburg-Lebanon, 19.43%) 14.51 $6,255 $9,257 $14,953 $975
11 King, WA (Seattle-Tacoma, 31.57%) Kittitas, WA (Rest of U.S., 17.06%) 14.51 $6,255 $9,257 $14,953 $4,869
12 Grundy, IL (Chicago-Naperville, 30.86%) Livingston, IL (Rest of U.S., 17.06%) 13.80 $5,949 $8,804 $14,221 $4,869
13 Weld, CO (Denver-Aurora, 30.52%) Morgan, CO (Rest of U.S., 17.06%) 13.46 $5,802 $8,587 $13,871 $4,869
14 Douglas, CO (Denver-Aurora, 30.52%) El Paso, CO (Colorado Springs, 20.15%) 10.37 $4,470 $6,615 $10,687 $0

Base rates used: GS-7 Step 1 $43,106, GS-11 Step 1 $63,795, GS-13 Step 5 $103,049, GS-15 Step 10 $164,301.

Two things jump out of the table.

The dollar gap is a pure function of the point spread. York/Cumberland PA and King/Kittitas WA sit on opposite coasts, but both carry a 14.51-point spread. They produce identical gaps at every grade: $6,255 at GS-7 and $14,953 at GS-13 Step 5. The counties do not matter. The spread does.

The cap flattens the top. Ten pairs land on exactly $4,869 at GS-15 Step 10 because the Rest of U.S. side totals $192,331 and every named area above roughly 20% is already pinned at $197,200. For Douglas vs. El Paso County, Colorado, both sides hit the cap, and a real 10-point cliff disappears entirely.

Where the Locality Pay Cliff Bites Hardest

Skip the GS-15 column when you judge the stakes. The cliff is widest in the middle of the scale, GS-11 through GS-14, where salaries are high enough for the percentage to matter but nobody is near the cap.

At GS-13 Step 5, the pairs run from $10,687 (Denver vs. Colorado Springs) to $30,173 (Calaveras vs. Tuolumne). That is the range a mid-career analyst, engineer, or contracting officer is actually living in, and it compounds every year.

It also compounds into retirement. Locality pay counts as basic pay for your High-3 average under 5 CFR 831.703. Take the Orange/Albemarle VA pair at GS-13 Step 5: a $17,395 salary gap becomes a roughly $17,400 High-3 gap if you finish your career there, and at the 1% FERS multiplier over 30 years, that is about $5,200 a year in pension, for life. Run your own numbers in the High-3 Calculator.

Three Assumptions the Thread Got Wrong

The Reddit thread that started this was mostly right about the mechanism. It got a few specifics wrong, and they are the same mistakes we see repeated everywhere.

"New Cumberland, PA gets DC money." New Cumberland sits in Cumberland County, PA. OPM places all of Cumberland County in the Harrisburg-Lebanon area at 19.43%, not Washington-Baltimore. The nearby York and Adams counties are in Washington-Baltimore, which is probably where the mix-up comes from. The cliff is real; the town is on the wrong side of it.

"The next county north of Albemarle is DC locality." The county due north of Albemarle, VA is Greene County, which is also Rest of U.S. The Washington-Baltimore neighbor is Orange County, to the northeast. The pair exists; the compass direction was off.

"Bakersfield must be a cheaper locality." Kern County, CA, including Bakersfield, is fully inside the Los Angeles locality at 36.47%. The cliff there runs the other way: cross into Tulare County (Fresno area, 17.65%) and a GS-13 Step 5 loses $19,394.

A fourth one shows up constantly: Providence, RI is not a separate, lower locality. All of Rhode Island belongs to Boston-Worcester-Providence at 32.58%. No cliff.

What You Can and Cannot Do About It

You cannot pick your locality area. It is a function of your duty station, and only your agency can change that. But the line does move in three legitimate ways.

Your agency moves your duty station. A reorganization, an office consolidation, or a change in your telework designation changes which county governs your rate. Agencies use this lever, and employees have no independent right to select a different area.

Your official worksite gets redesignated for telework. Under 5 CFR 531.605, a remote employee's home can become the official worksite. If your home county sits outside the higher-rate area, your locality rate drops with it. If you are hybrid and the agency office remains your official worksite, the office rate stays. Get the designation in writing before you move.

The Federal Salary Council adds your county. Rare, slow, and data-driven. Caroline County, VA joined Washington-Baltimore in 2024 after clearing the employee-count and commuting thresholds. Nothing changed for 2026, and the 2027 pay plan transmitted August 26 freezes every locality percentage at the 2026 level for most civilians, with a 3.8% carve-out for federal law enforcement. Unless Congress overrides that plan by December 11, the table above is also your 2027 table.

Calculate Your Locality Pay by Area

Pick your duty station area, grade, and step in the free GS Pay Calculator to see your exact 2026 salary. Each locality area has its own page with the full table: Washington-Baltimore, San Jose-San Francisco, Los Angeles, New York, Seattle, Denver, Houston, Boston, Chicago, Harrisburg, Colorado Springs, Fresno, and Rest of U.S..

Frequently Asked Questions

Is the viral $39,391 county-line locality pay example real?

Yes. We reproduced it from OPM's 2026 tables. It is the gap between Calaveras County, CA (San Jose-San Francisco-Oakland, 46.34%) and Tuolumne County, CA (Rest of U.S., 17.06%) at GS-15 Step 3, where the Calaveras side hits the $197,200 pay cap and the Tuolumne side does not.

Does my home county or my office county decide my locality pay?

Your official worksite decides it, not your home address. Under 5 CFR 531.604, the locality rate follows the duty station your agency has designated. If you drive from a Rest of U.S. county into a Washington-Baltimore locality office, you get the Washington-Baltimore rate.

If I telework from a cheaper county, do I lose my higher locality pay?

It depends on how your agency designated your official worksite under 5 CFR 531.605. If your home is your official worksite and it sits outside the higher-rate area, your rate drops to your home county's locality. If your agency office remains your official worksite, the office rate follows you.

Do locality pay county boundaries ever change?

Rarely, and only through the Federal Salary Council process. A single adjacent county needs 400 or more GS employees and a commuting interchange rate of at least 7.5% to be added to a neighboring locality area. OPM made no boundary changes anywhere in the country for 2026.

Does the federal pay cap make the county-line gap smaller at senior grades?

Yes, and sometimes it erases the gap. At GS-15 Step 10, ten of our fourteen pairs converge to the same $4,869 gap because the higher-locality side is already capped at $197,200. For Douglas County vs. El Paso County, Colorado, both sides hit the cap and the gap is $0.

Does the county-line difference carry into my FERS pension?

Yes. Locality pay counts as basic pay for your High-3 average under 5 CFR 831.703. Two employees with identical grades and careers who finish in counties on opposite sides of a locality line retire with different pensions, for life.

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