diff --git a/src/EFCore.Relational/Query/Pipeline/NullSemanticsRewritingVisitor.cs b/src/EFCore.Relational/Query/Pipeline/NullSemanticsRewritingVisitor.cs
index 6a65d27986b..66b6d8c61c3 100644
--- a/src/EFCore.Relational/Query/Pipeline/NullSemanticsRewritingVisitor.cs
+++ b/src/EFCore.Relational/Query/Pipeline/NullSemanticsRewritingVisitor.cs
@@ -171,8 +171,14 @@ private CaseExpression VisitCaseExpression(CaseExpression caseExpression)
 
         private SqlFunctionExpression VisitSqlFunctionExpression(SqlFunctionExpression sqlFunctionExpression)
         {
-            var newInstance = (SqlExpression)Visit(sqlFunctionExpression.Instance);
-            var isNullable = _isNullable;
+            var newInstance = default(SqlExpression);
+            var isNullable = false;
+            if (sqlFunctionExpression.Instance != null)
+            {
+                newInstance = (SqlExpression)Visit(sqlFunctionExpression.Instance);
+                isNullable = _isNullable;
+            }
+
             var newArguments = new SqlExpression[sqlFunctionExpression.Arguments.Count];
             for (var i = 0; i < newArguments.Length; i++)
             {
diff --git a/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.Functions.cs b/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.Functions.cs
index f2a8452a15c..cd516be73a3 100644
--- a/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.Functions.cs
+++ b/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.Functions.cs
@@ -843,7 +843,7 @@ public override async Task Where_string_to_upper(bool isAsync)
             AssertSql(
                 @"SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region]
 FROM [Customers] AS [c]
-WHERE (UPPER([c].[CustomerID]) = N'ALFKI') AND UPPER([c].[CustomerID]) IS NOT NULL");
+WHERE UPPER([c].[CustomerID]) = N'ALFKI'");
         }
 
         public override async Task Where_string_to_lower(bool isAsync)
@@ -853,7 +853,7 @@ public override async Task Where_string_to_lower(bool isAsync)
             AssertSql(
                 @"SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region]
 FROM [Customers] AS [c]
-WHERE (LOWER([c].[CustomerID]) = N'alfki') AND LOWER([c].[CustomerID]) IS NOT NULL");
+WHERE LOWER([c].[CustomerID]) = N'alfki'");
         }
 
         public override async Task Where_functions_nested(bool isAsync)
@@ -863,7 +863,7 @@ public override async Task Where_functions_nested(bool isAsync)
             AssertSql(
                 @"SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region]
 FROM [Customers] AS [c]
-WHERE (POWER(CAST(CAST(LEN([c].[CustomerID]) AS int) AS float), 2.0E0) = 25.0E0) AND POWER(CAST(CAST(LEN([c].[CustomerID]) AS int) AS float), 2.0E0) IS NOT NULL");
+WHERE POWER(CAST(CAST(LEN([c].[CustomerID]) AS int) AS float), 2.0E0) = 25.0E0");
         }
 
         public override async Task Convert_ToByte(bool isAsync)
diff --git a/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.cs b/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.cs
index e92efd08857..cad3024874e 100644
--- a/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.cs
+++ b/test/EFCore.SqlServer.FunctionalTests/Query/SimpleQuerySqlServerTest.cs
@@ -1153,7 +1153,7 @@ public override async Task Null_conditional_deep(bool isAsync)
             AssertSql(
                 @"SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region]
 FROM [Customers] AS [c]
-WHERE (CAST(LEN([c].[CustomerID]) AS int) = 5) AND CAST(LEN([c].[CustomerID]) AS int) IS NOT NULL");
+WHERE CAST(LEN([c].[CustomerID]) AS int) = 5");
         }
 
         public override async Task Queryable_simple(bool isAsync)
diff --git a/test/EFCore.Sqlite.FunctionalTests/Query/SimpleQuerySqliteTest.cs b/test/EFCore.Sqlite.FunctionalTests/Query/SimpleQuerySqliteTest.cs
index 7ec5989c51a..8647165eeb5 100644
--- a/test/EFCore.Sqlite.FunctionalTests/Query/SimpleQuerySqliteTest.cs
+++ b/test/EFCore.Sqlite.FunctionalTests/Query/SimpleQuerySqliteTest.cs
@@ -204,7 +204,7 @@ public override async Task Where_datetime_now(bool isAsync)
 
 SELECT ""c"".""CustomerID"", ""c"".""Address"", ""c"".""City"", ""c"".""CompanyName"", ""c"".""ContactName"", ""c"".""ContactTitle"", ""c"".""Country"", ""c"".""Fax"", ""c"".""Phone"", ""c"".""PostalCode"", ""c"".""Region""
 FROM ""Customers"" AS ""c""
-WHERE ((rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime'), '0'), '.') <> @__myDatetime_0) OR (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime'), '0'), '.') IS NULL OR @__myDatetime_0 IS NULL)) AND (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime'), '0'), '.') IS NOT NULL OR @__myDatetime_0 IS NOT NULL)");
+WHERE (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime'), '0'), '.') <> @__myDatetime_0) OR @__myDatetime_0 IS NULL");
         }
 
         public override async Task Where_datetime_utcnow(bool isAsync)
@@ -216,7 +216,7 @@ public override async Task Where_datetime_utcnow(bool isAsync)
 
 SELECT ""c"".""CustomerID"", ""c"".""Address"", ""c"".""City"", ""c"".""CompanyName"", ""c"".""ContactName"", ""c"".""ContactTitle"", ""c"".""Country"", ""c"".""Fax"", ""c"".""Phone"", ""c"".""PostalCode"", ""c"".""Region""
 FROM ""Customers"" AS ""c""
-WHERE ((rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now'), '0'), '.') <> @__myDatetime_0) OR (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now'), '0'), '.') IS NULL OR @__myDatetime_0 IS NULL)) AND (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now'), '0'), '.') IS NOT NULL OR @__myDatetime_0 IS NOT NULL)");
+WHERE (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now'), '0'), '.') <> @__myDatetime_0) OR @__myDatetime_0 IS NULL");
         }
 
         public override async Task Where_datetime_today(bool isAsync)
@@ -226,7 +226,7 @@ public override async Task Where_datetime_today(bool isAsync)
             AssertSql(
                 @"SELECT ""e"".""EmployeeID"", ""e"".""City"", ""e"".""Country"", ""e"".""FirstName"", ""e"".""ReportsTo"", ""e"".""Title""
 FROM ""Employees"" AS ""e""
-WHERE ((rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') = rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.')) AND (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') IS NOT NULL AND rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') IS NOT NULL)) OR (rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') IS NULL AND rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') IS NULL)");
+WHERE rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.') = rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', 'now', 'localtime', 'start of day'), '0'), '.')");
         }
 
         public override async Task Where_datetime_date_component(bool isAsync)
@@ -631,7 +631,7 @@ public override async Task Where_string_to_lower(bool isAsync)
             AssertSql(
                 @"SELECT ""c"".""CustomerID"", ""c"".""Address"", ""c"".""City"", ""c"".""CompanyName"", ""c"".""ContactName"", ""c"".""ContactTitle"", ""c"".""Country"", ""c"".""Fax"", ""c"".""Phone"", ""c"".""PostalCode"", ""c"".""Region""
 FROM ""Customers"" AS ""c""
-WHERE (lower(""c"".""CustomerID"") = 'alfki') AND lower(""c"".""CustomerID"") IS NOT NULL");
+WHERE lower(""c"".""CustomerID"") = 'alfki'");
         }
 
         public override async Task Where_string_to_upper(bool isAsync)
@@ -641,7 +641,7 @@ public override async Task Where_string_to_upper(bool isAsync)
             AssertSql(
                 @"SELECT ""c"".""CustomerID"", ""c"".""Address"", ""c"".""City"", ""c"".""CompanyName"", ""c"".""ContactName"", ""c"".""ContactTitle"", ""c"".""Country"", ""c"".""Fax"", ""c"".""Phone"", ""c"".""PostalCode"", ""c"".""Region""
 FROM ""Customers"" AS ""c""
-WHERE (upper(""c"".""CustomerID"") = 'ALFKI') AND upper(""c"".""CustomerID"") IS NOT NULL");
+WHERE upper(""c"".""CustomerID"") = 'ALFKI'");
         }
 
         public override async Task TrimStart_without_arguments_in_predicate(bool isAsync)