> For the complete documentation index, see [llms.txt](https://docs.premium-positioning.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.premium-positioning.com/learn/accuracy-expectations.md).

# Accuracy expectations

What accuracy to expect from RTK Premium in the field: 1 to 2 cm horizontal and sub-3 cm vertical in a fixed solution, and the conditions that affect it.

In a fixed solution under good GNSS conditions, RTK Premium positions to 1 to 2 cm horizontally and sub-3 cm vertically. The conditions below decide whether you get that result on the day, so they are worth planning around.

### Accuracy across the network

RTK Premium is network RTK on a virtual reference station model. The network models the ionospheric, tropospheric, and satellite orbit and clock errors from the reference stations around your rover, and builds a correction for where you are. Accuracy therefore depends far less on your distance to any one base station than it does with single-base RTK. It still varies with how closely the network's stations are spaced, which differs between networks and regions. See [What is network RTK and VRS](/learn/what-is-network-rtk-and-vrs.md).

Near the edge of coverage, run a fix test on site before committing to a full day of work.

### Sky view

* Best: open ground with no obstructions above about 15 degrees elevation.
* Good: rural areas with scattered trees.
* Challenging: near buildings or under partial tree canopy.
* Poor: urban canyons, dense forest, and large metal structures.

Multipath, where signals reflect off buildings, vehicles, or metal before reaching the antenna, biases the position even while the receiver reports fixed. See [Inconsistent RTK accuracy on site](/troubleshooting/inconsistent-rtk-accuracy-on-site.md).

### Data connection

Corrections have to arrive in real time, so the stability of the data link matters. Use a stable 4G or 5G connection, and watch the correction age on the receiver. A few seconds is normal; a rising age points to a struggling link.

### Receiver and antenna

A survey-grade or good mapping-grade receiver with a correctly measured antenna height gives the best and most repeatable results. A wrong antenna height adds the same vertical offset to every point.

### Heights

RTK gives ellipsoidal heights. If you need height above sea level, apply a geoid model in your software. See [Ellipsoidal and orthometric heights](/learn/ellipsoidal-and-orthometric-heights.md).

### Getting the best results

1. Work with a clear view of the sky.
2. Use a stable mobile data connection.
3. Wait for a stable fixed solution before collecting points.
4. When a result matters, measure a known point and compare it with its published coordinates.

### FAQ

How accurate is RTK Premium? In a fixed solution under good conditions, RTK Premium reaches 1 to 2 cm horizontally and sub-3 cm vertically.

How do I check the accuracy my service delivers? Measure a known point on site, or run a session on RTKTEST.com, which compares services against a surveyed point. See [Testing a correction service](/learn/testing-a-correction-service.md).

Does accuracy drop as I move away from a base station? It drops far less than with single-base RTK, because the network builds the correction for your position. Accuracy still varies with station spacing, so near the edge of coverage or where stations are sparse, test on site first.

Why is vertical accuracy lower than horizontal? All the satellites a receiver tracks are above the antenna, so the vertical component is less well constrained than the horizontal. This holds for all GNSS positioning, not only RTK.

My receiver reports fixed but the position is wrong. Why? A fixed status means the receiver believes it resolved the ambiguities, not that it resolved them correctly. See [Inconsistent RTK accuracy on site](/troubleshooting/inconsistent-rtk-accuracy-on-site.md).

Last updated: 10 October 2026