diff --git a/l10n/en-US/viewer.properties b/l10n/en-US/viewer.properties
index b545d0b9c69cb3..f75ceabbb9e31a 100644
--- a/l10n/en-US/viewer.properties
+++ b/l10n/en-US/viewer.properties
@@ -88,6 +88,12 @@ document_properties_version=PDF Version:
 document_properties_page_count=Page Count:
 document_properties_close=Close
 
+print_progress_message=Preparing document for printing…
+# LOCALIZATION NOTE (print_progress_percent): "{{progress}}" will be replaced by
+# a numerical per cent value.
+print_progress_percent={{progress}}%
+print_progress_close=Cancel
+
 # Tooltips and alt text for side panel toolbar buttons
 # (the _label strings are alt text for the buttons, the .title strings are
 # tooltips)
diff --git a/web/pdf_print_service.js b/web/pdf_print_service.js
index 2dd166db0016a2..95d00e425da171 100644
--- a/web/pdf_print_service.js
+++ b/web/pdf_print_service.js
@@ -28,6 +28,7 @@
       root.pdfjsWebOverlayManager, root.pdfjsWebApp, root.pdfjsWebPDFJS);
   }
 }(this, function (exports, uiUtils, overlayManager, app, pdfjsLib) {
+  var mozL10n = uiUtils.mozL10n;
   var CSS_UNITS = uiUtils.CSS_UNITS;
   var PDFPrintServiceFactory = app.PDFPrintServiceFactory;
   var OverlayManager = overlayManager.OverlayManager;
@@ -231,7 +232,8 @@
     var progressBar = progressContainer.querySelector('progress');
     var progressPerc = progressContainer.querySelector('.relative-progress');
     progressBar.value = progress;
-    progressPerc.textContent = progress + '%';
+    progressPerc.textContent = mozL10n.get('print_progress_percent',
+      {progress: progress}, progress + '%');
   }
 
   var hasAttachEvent = !!document.attachEvent;
diff --git a/web/viewer.html b/web/viewer.html
index 5f2c439fac433d..676b56cda6e08d 100644
--- a/web/viewer.html
+++ b/web/viewer.html
@@ -364,14 +364,14 @@
         <div id="printServiceOverlay" class="container hidden">
           <div class="dialog">
             <div class="row">
-              <span>Preparing document for printing...</span>
+              <span data-l10n-id="print_progress_message">Preparing document for printing…</span>
             </div>
             <div class="row">
               <progress value="0" max="100"></progress>
-              <span class="relative-progress">0%</span>
+              <span data-l10n-id="print_progress_percent" data-l10n-args='{ "progress": 0 }' class="relative-progress">0%</span>
             </div>
             <div class="buttonRow">
-              <button id="printCancel" class="overlayButton"><span>Cancel</span></button>
+              <button id="printCancel" class="overlayButton"><span data-l10n-id="print_progress_close">Cancel</span></button>
             </div>
           </div>
         </div>