REACH RS4

Fully-featured RTK receiver for surveying

Data collection with centimeter precision. Made for professionals.

$3,899

Buy Talk to the team

Fully-featured RTK receiver for surveying

High accuracy, even in the hardest spots

Reach RS4 gets a fixed solution in seconds. The receiver tracks GPS, GLONASS, Galileo, BeiDou, QZSS, and NavIC. All-band support and antenna with multipath rejection offers robust performance, even in harsh conditions.

7mm + 1 ppm in RTK

672 channels

L1/L2/L5/L6

Fits any workflow

Ready for data collection and design layout

Every Reach comes with the Emlid Flow app for iOS and Android. It helps you with every task on site, starting with laying out parcel corners and ending with documenting pipe attributes.

All projects are instantly synced to the cloud, meaning your team always has the latest updates and you always have a backup of your work.

Boundary mapping Topo survey Construction Utilities Landscaping

Set string lines and guide points.

Place reference points to guide construction and layout.

Record existing site features.

Document utilities, trees, and structures for planning or design.

Measure slopes and grades.

Check inclines for proper drainage or terrain adjustments.

Locate property corners.

Mark precise locations for building outlines or fence lines.

Verify features placement.

Confirm built elements match design plans accurately.

Mark out DXF designs.

Transfer points and lines to exact spots on site.

Mark centerlines, curves, and offsets.

Trace the exact paths for roads, pipelines, or structural elements.

Capture elevations and identify cut/fill zones.

Plan and check the earthwork.

Measure distances and angles precisely.

Determine exact distances and bearings between points for perfect alignment.

Join professional land surveyors using Reach devices

Francesco Pelazza, surveyor and geomatics professional, Italy

I’m working on topographic surveys and construction site measurements. In 2019, I integrated the Reach RS2 and Reach RS3 with my fleet, including total stations, to work in different environments. I often move from flat rural areas to mountain sites with no mobile internet coverage. With Reach receives, I perform surveys even when internet is not available, maintaining reliability and precision.

Marco Bartoletti, professional land surveyor, Italy

As a surveyor specializing in cadastral and boundary surveys, for years, I was relying on total stations which meant complex logistics and slow turnaround times. The turning point came with the shift to Emlid’s Reach RS3 and Reach RX receivers. These tools allowed me to manage the entire project directly in the field, reducing setup times and maintaining the high accuracy required for cadastral work.

Daniel Kenny, Survey Manager, KLS Earthworks, USA

Before introducing Emlid at KLS Earthwork, our field teams often called for a surveyor to check some data on site. There was always a wait time until a surveyor showed up. With the Emlid Reach receivers, projects are no longer delayed because supervisors can confirm grades and perform underground layout themselves. We increased productivity and decreased rework and wait time.

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Reach RS4: All-band RTK receiver with tilt compensation

Engineered to be tough, compact and lightweight

Reach RS4 receiver on a survey pole in a harsh outdoor environment

-20 to +65 ºС

Working temperature. Isn’t afraid of either heat or cold.

IP68

All connectors are completely sealed and protected from water and dust with silicone plugs.

16 hrs on one charge

Use the USB-C for recharging or use a power bank for even greater flexibility.

Magnesium alloy body

This material is often used for aerospace equipment. It strikes the perfect balance of durability and lightness.

129 x 129 x 99 mm

Fits in a small bag.

927 g

Weighs less than a typical survey pole.

Fast setup on worksite

Step 1

Choose the RTK source

You can place the local base, connect to Emlid Corrections or to an NTRIP service.

Step 2

Get a Fix

Configure the radio if you use a local base, the correction input if you choose NTRIP, or simply activate the Emlid Corrections.

Step 3

You’re all set

Now you can collect points and stake them out with the rover

Configure Reach receivers

Get corrections over internet

With the Reach RS4, you can access corrections over the internet by connecting to your local NTRIP network or by using built-in Emlid Corrections—a VRS-based correction service.

Use UHF or LoRa radio

Reach RS4 has a dual-band radio operating at 450 MHz and 915 MHz frequency. Suitable for both license and license-free connections.

Log raw data for PPK and PPP

Reach RS4 logs industry-standard RINEX files. Enable raw data recording to download and post-process it with popular PPK or PPP software.

Free lifetime support

Community

Join the Forum and Facebook User Group to connect with Emlid users from around the world and exchange experiences with other experts in your industry.

Expert assistance

When you choose the Reach RS4, you get lifetime access to our expert support team. We're here to help with anything you need within 24 hours or less.

We also provide video tutorials and quick-start guides, so you can learn at your own pace and make the most of your RS4.

Order your Reach RS4 today

Free year of RTK corrections

Reach RS4

Reach RS4, Case, USB-C cable

Buy Learn more

$3,899

Free year of RTK corrections

Emlid Base and Rover Kit

Reach RS4, Reach RS4 Pro, 2x Quick release adapter, Reach RS4 bumper, Reach RS4 Pro bumper

Buy Learn more

$8,870

2-7 days by FedEx, UPS

Online store Find a local dealer

Reach RS4 Datasheet
135 kb

Mechanical

Dimensions 128.6 x 128.6 x 99.3 mm
Weight 927 g (2.04 lb)
Operating temperatures -40 to +65 °C
Ingress protection IP68

Electrical

Autonomy 16 hrs as RTK rover with tilt
Battery Li-Ion 5000 mAh, 7.2 V
36 Wh
Charging USB Type-C (PD): 5V—3A
9V—3A, 12V—3A, 15V—3A

Positioning

Static H: 4 mm + 0.5 ppm
V: 8 mm + 1 ppm
PPK H: 5 mm + 0.5 ppm
V: 10 mm + 1 ppm
RTK H: 7 mm + 1 ppm
V: 14 mm + 1 ppm
Tilt compensation RTK + 2 mm + 0.3 mm/°
Convergence time ~5 s typically

Connectivity

Lora radio
Frequency range
Power
Distance
ㅤ
868/915 MHz
Up to 1W
Up to 8 km UHF radio
Frequency range
Power
Protocols
Modulation type
ㅤ
410–470 MHz
Up to 2W
TRIMTALK 450S**
GMSK
LTE modem Regions
Bands Global
FDD-LTE: 1, 2, 3, 4, 5,
7, 8, 12, 13,
18, 19, 20, 26, 28
TD-LTE: 38, 39, 40, 41
UMTS (UHPS/FDD):
1, 2, 5, 8
Quad-band, 850/1900
900/1800 MHz SIM card Nano-SIM
LTE modem Regions
Bands Global
FDD-LTE: 1, 2, 3, 4, 5,
7, 8, 12, 13,
18, 19, 20, 26, 28
TD-LTE: 38, 39, 40, 41
UMTS (UHPS/FDD):
1, 2, 5, 8
Quad-band, 850/1900
900/1800 MHz SIM card Nano-SIM
Wi-Fi 802.11a/b/g/n
Bluetooth 5.1 (BR/EDR + LE)
Ports RS-232, USB Type-C
*Use the correct antenna, LoRa or UHF, for your setup. **TRIMTALK is a trademark of Trimble Inc.

Data

Corrections NTRIP, RTCM3
Position output NMEA, LLH/XYZ
Data logging RINEX, NMEA, LLH/XYZ, UBX
Internal storage 16 GB

GNSS

Signal tracked GPS: L1C/A, L2C, L5,
GLONASS: L1OF, L2OF,
Galileo: E1-B/C, E5a, E6,
BeiDou: B1I, B1C, B2a, B3I,
QZSS: L1C/A, L1C/B11, L2C, L5,
NavIC: L1-SPS Data, L5-SPS
Number of channels 672
Update rates up to 10 Hz

Fill in the contact form, and we will reply within a working day (9:00-18:00 CET).

Toll Free: 888-454-1916

Direct Dial: +1 817 865 3334 (ex. 101)

sales@emlid.com

FAQ

What level of accuracy does the Reach RS4 deliver?

The Emlid Reach RS4 is built on a powerful, 672-channel all-band GNSS engine that tracks all major constellations (GPS, GLONASS, Galileo, BeiDou, QZSS, and NavIC). It provides 7mm + 1ppm horizontal and 14 + 1ppm vertical RTK accuracy. By tracking the lower L5 and L6 bands, the RS4 offers superior resistance to multipath interference and signal reflections. This allows surveyors to achieve a stable, centimeter-accurate Fix in roughly 5 seconds, even when working near tall buildings or under dense tree canopies.

How does the tilt compensation work, and does it require field calibration?

The Reach RS4 features a next-generation, IMU-based tilt compensation system that requires zero manual calibration. As it relies on an 6DOF IMU, without a magnetometer, the system is entirely immune to magnetic interference from nearby metal objects, vehicles, fences, or utility infrastructure. The receiver maintains sub-2cm precision even at steep inclination angles. The tilt correction activates automatically after just a few quick movements of the pole and remains stable throughout your entire job.

Can the Reach RS4 be used as a base and a rover? Is it compatible with third-party UHF receivers?

Yes. The Reach RS4 is a highly versatile unit that can act seamlessly as either a base station or a mobile rover. It features an expanded, internal 2W dual-band radio system. LoRa (868/915 MHz) is ideal for license-free, long-range base-to-rover communication up to 8 km (5 miles) when pairing two Emlid receivers. UHF (410–470 MHz) also provides native compatibility with third-party surveying equipment using the TRIMTALK 450S protocol.

What field software and file formats does the Reach RS4 support for CAD and GIS?

The receiver is powered by the Emlid Flow app (available for iOS and Android), which pairs instantly with the cloud-based Emlid Flow 360 platform for seamless field-to-office data synchronization. It supports all the standard workflows: collect topographic data, layout CAD designs, check cut/fill metrics, and stake out boundaries or centerlines. Data can be easily exported or imported in standard industry formats including CSV, DXF, and SHP.