diff --git a/src/core-uri-handlers.js b/src/core-uri-handlers.js
index 2af00f610..b2ddbbc25 100644
--- a/src/core-uri-handlers.js
+++ b/src/core-uri-handlers.js
@@ -1,9 +1,16 @@
+// Converts a query string parameter for a line or column number
+// to a zero-based line or column number for the Atom API.
+function getLineColNumber (numStr) {
+  const num = parseInt(numStr || 0, 10)
+  return Math.max(num - 1, 0)
+}
+
 function openFile (atom, {query}) {
   const {filename, line, column} = query
 
   atom.workspace.open(filename, {
-    initialLine: parseInt(line || 0, 10),
-    initialColumn: parseInt(column || 0, 10),
+    initialLine: getLineColNumber(line),
+    initialColumn: getLineColNumber(column),
     searchAllPanes: true
   })
 }