diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index c3396a70731..16b16732694 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -5079,6 +5079,14 @@
         "category": "Message",
         "code": 95080
     },
+    "Add 'const' to unresolved variable": {
+        "category": "Message",
+        "code": 95081
+    },
+    "Add 'const' to all unresolved variables": {
+        "category": "Message",
+        "code": 95082
+    },
     "No value exists in scope for the shorthand property '{0}'. Either declare one or provide an initializer.": {
         "category": "Error",
         "code": 18004
diff --git a/src/services/codefixes/addMissingConst.ts b/src/services/codefixes/addMissingConst.ts
new file mode 100644
index 00000000000..37739d01eee
--- /dev/null
+++ b/src/services/codefixes/addMissingConst.ts
@@ -0,0 +1,109 @@
+/* @internal */
+namespace ts.codefix {
+    const fixId = "addMissingConst";
+    const errorCodes = [
+        Diagnostics.Cannot_find_name_0.code,
+        Diagnostics.No_value_exists_in_scope_for_the_shorthand_property_0_Either_declare_one_or_provide_an_initializer.code
+    ];
+
+    registerCodeFix({
+        errorCodes,
+        getCodeActions: (context) => {
+            const changes = textChanges.ChangeTracker.with(context, t => makeChange(t, context.sourceFile, context.span.start, context.program));
+            if (changes.length > 0) {
+                return [createCodeFixAction(fixId, changes, Diagnostics.Add_const_to_unresolved_variable, fixId, Diagnostics.Add_const_to_all_unresolved_variables)];
+            }
+        },
+        fixIds: [fixId],
+        getAllCodeActions: context => {
+            const fixedNodes = new NodeSet();
+            return codeFixAll(context, errorCodes, (changes, diag) => makeChange(changes, diag.file, diag.start, context.program, fixedNodes));
+        },
+    });
+
+    function makeChange(changeTracker: textChanges.ChangeTracker, sourceFile: SourceFile, pos: number, program: Program, fixedNodes?: NodeSet<Node>) {
+        const token = getTokenAtPosition(sourceFile, pos);
+        const forInitializer = findAncestor(token, node =>
+            isForInOrOfStatement(node.parent) ? node.parent.initializer === node :
+            isPossiblyPartOfDestructuring(node) ? false : "quit"
+        );
+        if (forInitializer) return applyChange(changeTracker, forInitializer, sourceFile, fixedNodes);
+
+        const parent = token.parent;
+        if (isBinaryExpression(parent) && isExpressionStatement(parent.parent)) {
+            return applyChange(changeTracker, token, sourceFile, fixedNodes);
+        }
+
+        if (isArrayLiteralExpression(parent)) {
+            const checker = program.getTypeChecker();
+            if (!every(parent.elements, element => arrayElementCouldBeVariableDeclaration(element, checker))) {
+                return;
+            }
+
+            return applyChange(changeTracker, parent, sourceFile, fixedNodes);
+        }
+
+        const commaExpression = findAncestor(token, node =>
+            isExpressionStatement(node.parent) ? true :
+            isPossiblyPartOfCommaSeperatedInitializer(node) ? false : "quit"
+        );
+        if (commaExpression) {
+            const checker = program.getTypeChecker();
+            if (!expressionCouldBeVariableDeclaration(commaExpression, checker)) {
+                return;
+            }
+
+            return applyChange(changeTracker, commaExpression, sourceFile, fixedNodes);
+        }
+    }
+
+    function applyChange(changeTracker: textChanges.ChangeTracker, initializer: Node, sourceFile: SourceFile, fixedNodes?: NodeSet<Node>) {
+        if (!fixedNodes || fixedNodes.tryAdd(initializer)) {
+            changeTracker.insertModifierBefore(sourceFile, SyntaxKind.ConstKeyword, initializer);
+        }
+    }
+
+    function isPossiblyPartOfDestructuring(node: Node): boolean {
+        switch (node.kind) {
+            case SyntaxKind.Identifier:
+            case SyntaxKind.ArrayLiteralExpression:
+            case SyntaxKind.ObjectLiteralExpression:
+            case SyntaxKind.PropertyAssignment:
+            case SyntaxKind.ShorthandPropertyAssignment:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    function arrayElementCouldBeVariableDeclaration(expression: Expression, checker: TypeChecker): boolean {
+        const identifier =
+            isIdentifier(expression) ? expression :
+            isAssignmentExpression(expression, /*excludeCompoundAssignment*/ true) && isIdentifier(expression.left) ? expression.left :
+            undefined;
+        return !!identifier && !checker.getSymbolAtLocation(identifier);
+    }
+
+    function isPossiblyPartOfCommaSeperatedInitializer(node: Node): boolean {
+        switch (node.kind) {
+            case SyntaxKind.Identifier:
+            case SyntaxKind.BinaryExpression:
+            case SyntaxKind.CommaToken:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    function expressionCouldBeVariableDeclaration(expression: Node, checker: TypeChecker): boolean {
+        if (!isBinaryExpression(expression)) {
+            return false;
+        }
+
+        if (expression.operatorToken.kind === SyntaxKind.CommaToken) {
+            return every([expression.left, expression.right], expression => expressionCouldBeVariableDeclaration(expression, checker));
+        }
+
+        return isIdentifier(expression.left) && !checker.getSymbolAtLocation(expression.left);
+    }
+}
diff --git a/src/services/tsconfig.json b/src/services/tsconfig.json
index 681a9fc4b5e..5e6de0f15ca 100644
--- a/src/services/tsconfig.json
+++ b/src/services/tsconfig.json
@@ -45,6 +45,7 @@
         "codeFixProvider.ts",
         "refactorProvider.ts",
         "codefixes/addConvertToUnknownForNonOverlappingTypes.ts",
+        "codefixes/addMissingConst.ts",
         "codefixes/addMissingInvocationForDecorator.ts",
         "codefixes/addNameToNamelessParameter.ts",
         "codefixes/annotateWithTypeFromJSDoc.ts",
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForInLoop1.ts b/tests/cases/fourslash/codeFixAddMissingConstInForInLoop1.ts
new file mode 100644
index 00000000000..76b752465a9
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForInLoop1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////for (x in []) {}
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "for (const x in []) {}"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForInLoop2.ts b/tests/cases/fourslash/codeFixAddMissingConstInForInLoop2.ts
new file mode 100644
index 00000000000..03fb12f5d7e
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForInLoop2.ts
@@ -0,0 +1,12 @@
+/// <reference path='fourslash.ts' />
+
+////for (x in []) {}
+////for (y in []) {}
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: 
+`for (const x in []) {}
+for (const y in []) {}`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring1.ts b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring1.ts
new file mode 100644
index 00000000000..791615f5ea0
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////for ([x] of [[1,2]]) {}
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "for (const [x] of [[1,2]]) {}"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring2.ts b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring2.ts
new file mode 100644
index 00000000000..c0f8b733aec
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithArrayDestructuring2.ts
@@ -0,0 +1,12 @@
+/// <reference path='fourslash.ts' />
+
+////for ([x, y] of [[1,2]]) {}
+////for ([x] of [[1,2]]) {}
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: 
+`for (const [x, y] of [[1,2]]) {}
+for (const [x] of [[1,2]]) {}`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring1.ts b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring1.ts
new file mode 100644
index 00000000000..f926091da80
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////for ({ x } of [{ x: 0 }]) { }
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "for (const { x } of [{ x: 0 }]) { }"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring2.ts b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring2.ts
new file mode 100644
index 00000000000..aa8ec294972
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForLoopWithObjectDestructuring2.ts
@@ -0,0 +1,12 @@
+/// <reference path='fourslash.ts' />
+
+////for ({ x, y } of [{ x: 0, y: 1 }]) { }
+////for ({ x } of [{ x: 0 }]) { }
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: 
+`for (const { x, y } of [{ x: 0, y: 1 }]) { }
+for (const { x } of [{ x: 0 }]) { }`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop1.ts b/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop1.ts
new file mode 100644
index 00000000000..49efe2bc9a6
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////for (x of []) {}
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "for (const x of []) {}"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop2.ts b/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop2.ts
new file mode 100644
index 00000000000..24f8b48dfc9
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstInForOfLoop2.ts
@@ -0,0 +1,12 @@
+/// <reference path='fourslash.ts' />
+
+////for (x of []) {}
+////for (y of []) {}
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: 
+`for (const x of []) {}
+for (const y of []) {}`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation1.ts b/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation1.ts
new file mode 100644
index 00000000000..10818a621bb
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation1.ts
@@ -0,0 +1,19 @@
+/// <reference path='fourslash.ts' />
+
+////a = () => {
+////    x = 0;
+////    [y] = [1];
+////  weirdlyIndented = 2;
+////};
+////b = 3;
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: `const a = () => {
+    const x = 0;
+    const [y] = [1];
+  const weirdlyIndented = 2;
+};
+const b = 3;`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation2.ts b/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation2.ts
new file mode 100644
index 00000000000..1411dc357e1
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstPreservingIndentation2.ts
@@ -0,0 +1,19 @@
+/// <reference path='fourslash.ts' />
+
+////a = () => {
+////    for (x in []) {
+////        y = 0;
+////    }
+////};
+////b = 3;
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: `const a = () => {
+    for (const x in []) {
+        const y = 0;
+    }
+};
+const b = 3;`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring1.ts b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring1.ts
new file mode 100644
index 00000000000..8e40466c3ba
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////[x] = [0];
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "const [x] = [0];"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring2.ts b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring2.ts
new file mode 100644
index 00000000000..57a89076cb2
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring2.ts
@@ -0,0 +1,9 @@
+/// <reference path='fourslash.ts' />
+
+////[x, y] = [0, 1];
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: "const [x, y] = [0, 1];"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring3.ts b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring3.ts
new file mode 100644
index 00000000000..4099e1fe473
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring3.ts
@@ -0,0 +1,6 @@
+/// <reference path='fourslash.ts' />
+
+////let x: any;
+////[x, y] = [0, 1];
+
+verify.not.codeFixAvailable();
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring4.ts b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring4.ts
new file mode 100644
index 00000000000..2c077e4c149
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToArrayDestructuring4.ts
@@ -0,0 +1,5 @@
+/// <reference path='fourslash.ts' />
+
+////[x, y()] = [0, () => 1];
+
+verify.not.codeFixAvailable();
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer1.ts b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer1.ts
new file mode 100644
index 00000000000..c5bb309698d
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer1.ts
@@ -0,0 +1,9 @@
+/// <reference path='fourslash.ts' />
+
+////x = 0, y = 0;
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: "const x = 0, y = 0;"
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer2.ts b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer2.ts
new file mode 100644
index 00000000000..1a60b16489d
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer2.ts
@@ -0,0 +1,11 @@
+/// <reference path='fourslash.ts' />
+
+////x = 0,
+////y = 0;
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: `const x = 0,
+y = 0;`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer3.ts b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer3.ts
new file mode 100644
index 00000000000..d39388af335
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer3.ts
@@ -0,0 +1,15 @@
+/// <reference path='fourslash.ts' />
+
+////function f() { return 42; }
+////x = 0, y = f()
+////
+////, z = 0;
+
+verify.codeFixAll({
+    fixId: "addMissingConst",
+    fixAllDescription: "Add 'const' to all unresolved variables",
+    newFileContent: `function f() { return 42; }
+const x = 0, y = f()
+
+, z = 0;`
+});
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer4.ts b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer4.ts
new file mode 100644
index 00000000000..263ed33231a
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToCommaSeparatedInitializer4.ts
@@ -0,0 +1,6 @@
+/// <reference path='fourslash.ts' />
+
+////let y: any;
+////x = 0, y = 0;
+
+verify.not.codeFixAvailable();
diff --git a/tests/cases/fourslash/codeFixAddMissingConstToStandaloneIdentifier1.ts b/tests/cases/fourslash/codeFixAddMissingConstToStandaloneIdentifier1.ts
new file mode 100644
index 00000000000..0a603dced30
--- /dev/null
+++ b/tests/cases/fourslash/codeFixAddMissingConstToStandaloneIdentifier1.ts
@@ -0,0 +1,8 @@
+/// <reference path='fourslash.ts' />
+
+////x = 0;
+
+verify.codeFix({
+    description: "Add 'const' to unresolved variable",
+    newFileContent: "const x = 0;"
+});