diff --git a/src/Psalm/Checker/FunctionLikeChecker.php b/src/Psalm/Checker/FunctionLikeChecker.php
index 518c5cef6..3b3bfa801 100644
--- a/src/Psalm/Checker/FunctionLikeChecker.php
+++ b/src/Psalm/Checker/FunctionLikeChecker.php
@@ -944,7 +944,14 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
 
             $return_types_different = false;
 
-            if (!TypeChecker::isContainedBy($inferred_return_type, $declared_return_type, $this->getFileChecker())) {
+            if (!TypeChecker::isContainedBy(
+                $inferred_return_type,
+                $declared_return_type,
+                $this->getFileChecker(),
+                false,
+                $has_scalar_match,
+                $type_coerced
+            )) {
                 if ($update_docblock) {
                     if (!in_array('InvalidReturnType', $this->suppressed_issues)) {
                         FileChecker::addDocblockReturnType(
@@ -968,9 +975,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                 }
 
                 // is the declared return type more specific than the inferred one?
-                if ($declared_return_type->isNullable() === $inferred_return_type->isNullable() &&
-                    TypeChecker::isContainedBy($declared_return_type, $inferred_return_type, $this->getFileChecker())
-                ) {
+                if ($declared_return_type->isNullable() === $inferred_return_type->isNullable() && $type_coerced) {
                     if (IssueBuffer::accepts(
                         new MoreSpecificReturnType(
                             'The given return type \'' . $declared_return_type . '\' for ' . $cased_method_id .
diff --git a/src/Psalm/Checker/TypeChecker.php b/src/Psalm/Checker/TypeChecker.php
index 139655099..cfc36dd97 100644
--- a/src/Psalm/Checker/TypeChecker.php
+++ b/src/Psalm/Checker/TypeChecker.php
@@ -790,6 +790,12 @@ class TypeChecker
                             $container_type_part->value
                         )
                     ) ||
+                    (InterfaceChecker::interfaceExists($input_type_part->value, $file_checker) &&
+                        InterfaceChecker::interfaceExtends(
+                            $input_type_part->value,
+                            $container_type_part->value
+                        )
+                    ) ||
                     ExpressionChecker::isMock($input_type_part->value)
                 )
             )
@@ -914,11 +920,19 @@ class TypeChecker
             return true;
         } elseif ($container_type_part instanceof TNamedObject &&
             $input_type_part instanceof TNamedObject &&
-            ClassChecker::classExists($container_type_part->value, $file_checker) &&
             ClassChecker::classOrInterfaceExists($input_type_part->value, $file_checker) &&
-            ClassChecker::classExtendsOrImplements(
-                $container_type_part->value,
-                $input_type_part->value
+            ((
+                ClassChecker::classExists($container_type_part->value, $file_checker) &&
+                    ClassChecker::classExtendsOrImplements(
+                        $container_type_part->value,
+                        $input_type_part->value
+                )) ||
+                (InterfaceChecker::interfaceExists($container_type_part->value, $file_checker) &&
+                    InterfaceChecker::interfaceExtends(
+                        $container_type_part->value,
+                        $input_type_part->value
+                    )
+                )
             )
         ) {
             $type_coerced = true;
diff --git a/tests/ClassTest.php b/tests/ClassTest.php
index a284c3520..9b60a3690 100644
--- a/tests/ClassTest.php
+++ b/tests/ClassTest.php
@@ -566,4 +566,24 @@ class ClassTest extends PHPUnit_Framework_TestCase
         $context = new Context();
         $file_checker->visitAndAnalyzeMethods($context);
     }
+
+    /**
+     * @expectedException        \Psalm\Exception\CodeException
+     * @expectedExceptionMessage MoreSpecificReturnType
+     * @return                   void
+     */
+    public function testMoreSpecificReturnType()
+    {
+        $stmts = self::$parser->parse('<?php
+        class A {}
+        class B extends A {}
+
+        function foo(A $a) : B {
+            return $a;
+        }
+        ');
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
 }
diff --git a/tests/InterfaceTest.php b/tests/InterfaceTest.php
index f25d724ef..393c3f660 100644
--- a/tests/InterfaceTest.php
+++ b/tests/InterfaceTest.php
@@ -544,4 +544,42 @@ class InterfaceTest extends PHPUnit_Framework_TestCase
         $context = new Context();
         $file_checker->visitAndAnalyzeMethods($context);
     }
+
+    /**
+     * @return void
+     */
+    public function testInterfaceExtendsReturnType()
+    {
+        $stmts = self::$parser->parse('<?php
+        interface A {}
+        interface B extends A {}
+
+        function foo(B $a) : A {
+            return $a;
+        }
+        ');
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
+
+    /**
+     * @expectedException        \Psalm\Exception\CodeException
+     * @expectedExceptionMessage MoreSpecificReturnType
+     * @return                   void
+     */
+    public function testMoreSpecificReturnType()
+    {
+        $stmts = self::$parser->parse('<?php
+        interface A {}
+        interface B extends A {}
+
+        function foo(A $a) : B {
+            return $a;
+        }
+        ');
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
 }