Big changes are coming in 2026 to the geodetic reference systems “datums” behind GPS and if you're using GPS for precision ag, surveying, or construction, these changes may affect your A-B lines, boundaries, and other mapped data.

The National Geodetic Survey (NGS) will officially replace two outdated reference frames:

  • NAD 83 (2011) → will be replaced by NATRF2022 for latitude and longitude positioning
  • NAVD 88 → will be replaced by NAPGD2022 for elevational positioning

This is part of a modernization of the National Spatial Reference System (NSRS), the framework that underpins how all GPS-based coordinates are calculated in North America.

So, what does this mean for you? Let’s break it down.

Why the Change?

The current systems are shifted and need to be corrected:

  • NAD 83 is off by about 2.2 meters from the Earth’s actual center.
  • NAVD 88 has a tilted vertical bias, off by up to 1 meter in places.

The new datums will align better with global positioning systems (like Galileo and GLONASS), providing improved accuracy and reducing discrepancies across different platforms.

What's the Actual Impact?

In simple terms: your coordinates, depending on your GPS system, could move.

Shifts of up to 1–4 meters are possible, depending on your location and what system you use.

If you’re working with precision field boundaries, A-B lines, elevation data, or RTK correction networks, this could mean:

  • Mapped features appearing in the wrong location
  • Auto-steer A-B lines drifting off course
  • Field edges no longer matching the real-world layout

Who Needs to Pay Attention?

Not everyone will feel this shift equally. Here’s how to know if you’ll be affected:

You won’t notice much change if:

  • You’re using WAAS or similar SBAS corrections. These aren’t accurate enough to track 1-2 meter changes, and most users aren’t tracking high-precision boundaries anyway.
  • You’re on a major commercial satellite RTK platform (like Trimble, John Deere, etc.) that already aligns to a global datum.

You will be impacted if:

  • You rely on a local RTK base station that you’ve set up using NAD 83 coordinates
  • You use a state-run RTN (like the Iowa RTN) that references NAD 83 or NAVD 88
  • You’ve mapped and saved field boundaries, A-B lines, or tile plans using legacy systems and expect them to align perfectly in 2026 and beyond
  • You’re a surveyor, engineer, or GIS professional working with local benchmarks or design data

If you’re using the IARTN CORS network, you’ll definitely want to plan ahead, as your reference positions will shift, and field alignments may no longer match.

3 Options to Handle the Shift

Here’s how to get ready, based on guidance from the NGS:

1. Resurvey

  • What it is: Physically re-collect GPS coordinates for field boundaries, control points, or benchmarks using a system aligned to the new datum.
  • Best for: Anyone who needs the highest accuracy row crop spacing, tiling, drainage systems, or structural placement.

2. Readjust

  • What it is: Recalculate your data using updated reference points or transformation software.
  • Best for: Surveyors, GIS users, or farm managers with large datasets they want to preserve.

3. Transform

  • What it is: Use the free NGS Coordinate Conversion and Transformation Tool (NCAT) to shift coordinates from NAD 83/NAVD 88 to NATRF2022.
  • Best for: Quick updates to field boundaries, A-B lines, or checking impact on existing data.

Example: How this Might Affect a Farmer

A grower in Eastern Iowa has been using a local RTK base station tied to NAD 83 to map field edges with sub-inch accuracy to avoid his neighbor’s fence line. After 2026, the new NATRF2022 datum will shift those GPS-defined boundaries by several feet. While the fence hasn’t moved, the guidance lines now show up partially in the neighbor’s field. Without correction, auto-steer will drift across actual property lines.

Before spring 2026, you should:

  • Back up all current GPS files and data
  • Talk to your equipment dealer about firmware updates or new coordinate system support
  • Use NCAT or dealer provided tools to test a few key points and see how much they move
  • Consider a quick resurvey for high-value areas

Final Thoughts: Don't Wait!

NAD 83 and NAVD 88 won’t disappear overnight, but relying on outdated systems will only get more confusing and less compatible with time.

Taking a little time now to understand how your equipment references position data will save you headaches (and potential errors) down the road.

For more info, check out the NGS “Get Prepared” resource: Get Prepared | New Datums | National Geodetic Survey