diff --git a/application/views/contesting/index.php b/application/views/contesting/index.php
index e1e3cc5f..1ca451bd 100644
--- a/application/views/contesting/index.php
+++ b/application/views/contesting/index.php
@@ -102,7 +102,7 @@
                         <div class="row">
                             <div class="mb-3 col-md-3">
                                 <label for="callsign"><?php echo lang('gen_hamradio_callsign'); ?></label>
-                                <input type="text" class="form-control form-control-sm" id="callsign" name="callsign" required>
+                                <input type="text" class="form-control form-control-sm" id="callsign" name="callsign" required pattern="\S+" title="Whitespace is not allowed">
                                 <small id="callsign_info" class="badge text-bg-danger"></small>
                             </div>
 
diff --git a/assets/js/sections/contesting.js b/assets/js/sections/contesting.js
index 7a30890d..10d225b8 100644
--- a/assets/js/sections/contesting.js
+++ b/assets/js/sections/contesting.js
@@ -433,7 +433,7 @@ function logQso() {
 
 		var data = [[
 			$("#start_date").val() + ' ' + $("#start_time").val(),
-			$("#callsign").val().toUpperCase(),
+			$("#callsign").val($("#callsign").val().replace(/\s+/g, '').toUpperCase()),
 			$("#band").val(),
 			$("#mode").val(),
 			$("#rst_sent").val(),