diff --git a/html/about.html b/html/about.html
index 09794ca..a7acedf 100644
--- a/html/about.html
+++ b/html/about.html
@@ -53,6 +53,10 @@ <h3>Device<br></h3>
                                 <td>API Identifier</td>
                                 <td id="APIID">{{.DeviceID}}</td>
                             </tr>
+                            <tr>
+                                <td>Last Salt Update</td>
+                                <td>{{.LastSaltUpdate}}</td>
+                            </tr>
                         </tbody>
                     </table>
                 </div>
@@ -103,4 +107,4 @@ <h3>Installed Packages<br></h3>
 
 </body>
 
-</html>
\ No newline at end of file
+</html>
diff --git a/management-interface.go b/management-interface.go
index e01e26e..eb06d1a 100644
--- a/management-interface.go
+++ b/management-interface.go
@@ -36,6 +36,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"time"
 
 	goconfig "github.com/TheCacophonyProject/go-config"
 
@@ -125,18 +126,34 @@ func getRaspberryPiSerialNumber() string {
 
 // Return the salt minion ID for the device.
 func getSaltMinionID() string {
+	return strings.TrimSpace(readFile("/etc/salt/minion_id"))
+}
 
+// Return the time of the last salt update.
+func getLastSaltUpdate() string {
+	timeStr := strings.TrimSpace(readFile("/etc/cacophony/last-salt-update"))
+	if timeStr == "" {
+		return ""
+	}
+	t, err := time.Parse(time.RFC3339, timeStr)
+	if err != nil {
+		return ""
+	}
+	return t.Format("2006-01-02 15:04:05")
+}
+
+// Return context from file returning an empty string if on windows or if read fails
+func readFile(file string) string {
 	if runtime.GOOS == "windows" {
 		return ""
 	}
 
 	// The /etc/salt/minion_id file contains the ID.
-	out, err := ioutil.ReadFile("/etc/salt/minion_id")
+	out, err := ioutil.ReadFile(file)
 	if err != nil {
 		return ""
 	}
-
-	return strings.TrimSpace(string(out))
+	return string(out)
 }
 
 // Get the directory of where this executable was started.
@@ -607,6 +624,7 @@ func AboutHandler(w http.ResponseWriter, r *http.Request, conf *goconfig.Config)
 		SaltMinionID            string
 		Group                   string
 		DeviceID                int
+		LastSaltUpdate          string
 		PackageDataRows         [][]string
 		ErrorMessage            string
 	}
@@ -626,6 +644,7 @@ func AboutHandler(w http.ResponseWriter, r *http.Request, conf *goconfig.Config)
 		SaltMinionID:            getSaltMinionID(),
 		Group:                   device.Group,
 		DeviceID:                device.ID,
+		LastSaltUpdate:          getLastSaltUpdate(),
 	}
 
 	// Get installed packages.