diff --git a/ui/messages.go b/ui/messages.go
index cce384f..816c3c6 100644
--- a/ui/messages.go
+++ b/ui/messages.go
@@ -19,9 +19,16 @@ import (
 
 //======================================================================
 
+// For fixing off-by-one errors in packet marks
+var funcMap = template.FuncMap{
+	"inc": func(i int) int {
+		return i + 1
+	},
+}
+
 var TemplateData map[string]interface{}
 
-var Templates = template.Must(template.New("Help").Parse(`
+var Templates = template.Must(template.New("Help").Funcs(funcMap).Parse(`
 {{define "NameVer"}}termshark {{.Version}}{{end}}
 {{define "TsharkVer"}}using tshark {{.TsharkVersion}} (from {{.TsharkAbsolutePath}}){{end}}
 
@@ -88,10 +95,10 @@ left     - Widen selection
 right    - Narrow selection{{end}}
 '?'      - Display copy-mode help
 {{define "Marks"}}{{if not .Marks}}No local marks are set{{else}}Mark Packet Summary{{range $key, $value := .Marks }}
-{{printf " %c" $key}}{{printf "%6d" $value.Pos}}    {{printf "%s" $value.Summary}}{{end}}{{end}}
+{{printf " %c" $key}}{{printf "%6d" (inc $value.Pos)}}    {{printf "%s" $value.Summary}}{{end}}{{end}}
 
 {{if not .GlobalMarks}}No cross-file marks are set{{else}}Mark Packet  File              Summary{{range $key, $value := .GlobalMarks }}
-{{printf " %-4c" $key}} {{printf "%-7d" $value.Pos}}{{printf "%-18s" $value.Base}}{{printf "%s" $value.Summary}}{{end}}{{end}}{{end}}
+{{printf " %-4c" $key}} {{printf "%-7d" (inc $value.Pos)}}{{printf "%-18s" $value.Base}}{{printf "%s" $value.Summary}}{{end}}{{end}}{{end}}
 {{define "Key Mappings"}}{{if .Maps.None}}No key mappings are set{{else}}  From          To   {{range $mapping := .Maps.Get }}
 {{printf "  %-14v" $mapping.From}}{{printf "%v" $mapping.To}}   {{end}}{{end}}
 {{end}}