diff --git a/internal/lang/funcs/descriptions.go b/internal/lang/funcs/descriptions.go
index 2494f4e2ca..1ffcae81e9 100644
--- a/internal/lang/funcs/descriptions.go
+++ b/internal/lang/funcs/descriptions.go
@@ -177,6 +177,10 @@ var DescriptionList = map[string]descriptionEntry{
 		Description:      "`endswith` takes two values: a string to check and a suffix string. The function returns true if the first string ends with that exact suffix.",
 		ParamDescription: []string{"", ""},
 	},
+	"ephemeralasnull": {
+		Description:      "`ephemeralasnull` replaces any ephemeral values in the given value with a null value of the corresponding type.",
+		ParamDescription: []string{""},
+	},
 	"file": {
 		Description:      "`file` reads the contents of a file at the given path and returns them as a string.",
 		ParamDescription: []string{""},
diff --git a/internal/lang/funcs/ephemeral.go b/internal/lang/funcs/ephemeral.go
new file mode 100644
index 0000000000..5fe2e9b678
--- /dev/null
+++ b/internal/lang/funcs/ephemeral.go
@@ -0,0 +1,63 @@
+// Copyright (c) The OpenTofu Authors
+// SPDX-License-Identifier: MPL-2.0
+// Copyright (c) 2023 HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package funcs
+
+import (
+	"github.com/opentofu/opentofu/internal/lang/marks"
+	"github.com/zclconf/go-cty/cty"
+	"github.com/zclconf/go-cty/cty/function"
+)
+
+var EphemeralAsNullFunc = function.New(&function.Spec{
+	Params: []function.Parameter{
+		{
+			Name:             "value",
+			Type:             cty.DynamicPseudoType,
+			AllowUnknown:     true,
+			AllowNull:        true,
+			AllowMarked:      true,
+			AllowDynamicType: true,
+		},
+	},
+	Type: func(args []cty.Value) (cty.Type, error) {
+		// The result type is always the same as the argument type.
+		return args[0].Type(), nil
+	},
+	Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) {
+		return cty.Transform(args[0], func(_ cty.Path, val cty.Value) (cty.Value, error) {
+			ty := val.Type()
+
+			// Preserve non-ephemeral marks
+			nonEphemeralMarks := val.Marks()
+			delete(nonEphemeralMarks, marks.Ephemeral)
+
+			switch {
+			case val.IsNull():
+				return cty.NullVal(ty).WithMarks(nonEphemeralMarks), nil
+			case !val.IsKnown():
+				// This mirrors the logic in IsSensitive()
+				//
+				// When a value is unknown its ephemerality is also not yet
+				// finalized, because authors can write expressions where the
+				// ephemerality of the result is decided based on some other
+				// value that isn't yet known itself. As a simple example:
+				//    var.unknown_bool ? var.some_ephemeral_value : "b"
+				//
+				// Therefore we must report that we can't predict whether an
+				// unknown value will be ephemeral or not. For more information,
+				// refer to https://github.com/opentofu/opentofu/issues/2415
+
+				return cty.UnknownVal(val.Type()).WithMarks(nonEphemeralMarks), nil
+			case val.HasMark(marks.Ephemeral):
+				// This whole value is marked as ephemeral and should be null
+				return cty.NullVal(val.Type()).WithMarks(nonEphemeralMarks), nil
+			default:
+				// Not marked
+				return val, nil
+			}
+		})
+	},
+})
diff --git a/internal/lang/funcs/ephemeral_test.go b/internal/lang/funcs/ephemeral_test.go
new file mode 100644
index 0000000000..f21595da86
--- /dev/null
+++ b/internal/lang/funcs/ephemeral_test.go
@@ -0,0 +1,128 @@
+// Copyright (c) The OpenTofu Authors
+// SPDX-License-Identifier: MPL-2.0
+// Copyright (c) 2023 HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package funcs
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/opentofu/opentofu/internal/lang/marks"
+	"github.com/zclconf/go-cty/cty"
+)
+
+func TestEphemeralAsNullFunc(t *testing.T) {
+	// This is a bit overkill, but it is better to be explicit
+	cases := []struct {
+		Name     string
+		Input    cty.Value
+		Expected cty.Value
+	}{
+		{"null",
+			cty.NullVal(cty.String),
+			cty.NullVal(cty.String)},
+		{"null_sensitive",
+			cty.NullVal(cty.String).Mark(marks.Sensitive),
+			cty.NullVal(cty.String).Mark(marks.Sensitive)},
+		{"null_ephemeral",
+			cty.NullVal(cty.String).Mark(marks.Ephemeral),
+			cty.NullVal(cty.String)},
+		{"null_complex",
+			cty.NullVal(cty.String).Mark(marks.Ephemeral).Mark(marks.Sensitive),
+			cty.NullVal(cty.String).Mark(marks.Sensitive)},
+		{"unknown",
+			cty.UnknownVal(cty.String),
+			cty.UnknownVal(cty.String)},
+		{"unknown_sensitive",
+			cty.UnknownVal(cty.String).Mark(marks.Sensitive),
+			cty.UnknownVal(cty.String).Mark(marks.Sensitive)},
+		{"unknown_ephemeral",
+			cty.UnknownVal(cty.String).Mark(marks.Ephemeral),
+			cty.UnknownVal(cty.String)},
+		{"unknown_complex",
+			cty.UnknownVal(cty.String).Mark(marks.Ephemeral).Mark(marks.Sensitive),
+			cty.UnknownVal(cty.String).Mark(marks.Sensitive)},
+		{"primitive",
+			cty.StringVal("myprimitive"),
+			cty.StringVal("myprimitive")},
+		{"primitive_sensitive",
+			cty.StringVal("mysensitive").Mark(marks.Sensitive),
+			cty.StringVal("mysensitive").Mark(marks.Sensitive)},
+		{"primitive_ephemeral",
+			cty.StringVal("myephemeral").Mark(marks.Ephemeral),
+			cty.NullVal(cty.String)},
+		{"list",
+			cty.ListVal([]cty.Value{cty.StringVal("val")}),
+			cty.ListVal([]cty.Value{cty.StringVal("val")})},
+		{"list_sensitive",
+			cty.ListVal([]cty.Value{cty.StringVal("val")}).Mark(marks.Sensitive),
+			cty.ListVal([]cty.Value{cty.StringVal("val")}).Mark(marks.Sensitive)},
+		{"list_ephemeral",
+			cty.ListVal([]cty.Value{cty.StringVal("val")}).Mark(marks.Ephemeral),
+			cty.NullVal(cty.List(cty.String))},
+		{"list_complex",
+			cty.ListVal([]cty.Value{cty.StringVal("val")}).Mark(marks.Ephemeral).Mark(marks.Sensitive),
+			cty.NullVal(cty.List(cty.String)).Mark(marks.Sensitive)},
+		{"listcontents_sensitive",
+			cty.ListVal([]cty.Value{cty.StringVal("val").Mark(marks.Sensitive)}),
+			cty.ListVal([]cty.Value{cty.StringVal("val").Mark(marks.Sensitive)})},
+		{"listcontents_ephemeral",
+			cty.ListVal([]cty.Value{cty.StringVal("val").Mark(marks.Ephemeral)}),
+			cty.ListVal([]cty.Value{cty.NullVal(cty.String)})},
+		{"listcontents_complex",
+			cty.ListVal([]cty.Value{cty.StringVal("val").Mark(marks.Ephemeral).Mark(marks.Sensitive)}),
+			cty.ListVal([]cty.Value{cty.NullVal(cty.String).Mark(marks.Sensitive)})},
+		{"listcontents_multiple",
+			cty.ListVal([]cty.Value{cty.StringVal("val").Mark(marks.Ephemeral).Mark(marks.Sensitive), cty.StringVal("other")}),
+			cty.ListVal([]cty.Value{cty.NullVal(cty.String).Mark(marks.Sensitive), cty.StringVal("other")})},
+		{"listempty",
+			cty.ListValEmpty(cty.String),
+			cty.ListValEmpty(cty.String)},
+		{"listempty_sensitive",
+			cty.ListValEmpty(cty.String).Mark(marks.Sensitive),
+			cty.ListValEmpty(cty.String).Mark(marks.Sensitive)},
+		{"listempty_ephemeral",
+			cty.ListValEmpty(cty.String).Mark(marks.Ephemeral),
+			cty.NullVal(cty.List(cty.String))},
+		{"listempty_complex",
+			cty.ListValEmpty(cty.String).Mark(marks.Ephemeral).Mark(marks.Sensitive),
+			cty.NullVal(cty.List(cty.String)).Mark(marks.Sensitive)},
+		{"map",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")}),
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")})},
+		{"map_sensitive",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")}).Mark(marks.Sensitive),
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")}).Mark(marks.Sensitive)},
+		{"map_ephemeral",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")}).Mark(marks.Ephemeral),
+			cty.NullVal(cty.Map(cty.String))},
+		{"map_complex",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val")}).Mark(marks.Ephemeral).Mark(marks.Sensitive),
+			cty.NullVal(cty.Map(cty.String)).Mark(marks.Sensitive)},
+		{"mapcontents_sensitive",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val").Mark(marks.Sensitive)}),
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val").Mark(marks.Sensitive)})},
+		{"mapcontents_ephemeral",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val").Mark(marks.Ephemeral)}),
+			cty.MapVal(map[string]cty.Value{"key": cty.NullVal(cty.String)})},
+		{"mapcontents_complex",
+			cty.MapVal(map[string]cty.Value{"key": cty.StringVal("val").Mark(marks.Ephemeral).Mark(marks.Sensitive)}),
+			cty.MapVal(map[string]cty.Value{"key": cty.NullVal(cty.String).Mark(marks.Sensitive)})},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.Name, func(t *testing.T) {
+			out, err := EphemeralAsNullFunc.Call([]cty.Value{tc.Input})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !reflect.DeepEqual(tc.Expected, out) {
+				t.Fatalf("Expected %#v, Got %#v", tc.Expected, out)
+			}
+		})
+	}
+
+}
diff --git a/internal/lang/functions.go b/internal/lang/functions.go
index 7ad69d0078..a7c6cbd22c 100644
--- a/internal/lang/functions.go
+++ b/internal/lang/functions.go
@@ -146,6 +146,7 @@ func makeBaseFunctionTable(baseDir string) map[string]function.Function {
 		"distinct":         stdlib.DistinctFunc,
 		"element":          stdlib.ElementFunc,
 		"endswith":         funcs.EndsWithFunc,
+		"ephemeralasnull":  funcs.EphemeralAsNullFunc,
 		"chunklist":        stdlib.ChunklistFunc,
 		"file":             funcs.MakeFileFunc(baseDir, false),
 		"fileexists":       funcs.MakeFileExistsFunc(baseDir),
diff --git a/internal/lang/functions_test.go b/internal/lang/functions_test.go
index a4a5313cdb..11a11bcdad 100644
--- a/internal/lang/functions_test.go
+++ b/internal/lang/functions_test.go
@@ -376,7 +376,13 @@ func TestFunctions(t *testing.T) {
 				cty.False,
 			},
 		},
-
+		"ephemeralasnull": {
+			{
+				// We have more specific tests in the funcs package
+				`ephemeralasnull("foo")`,
+				cty.StringVal("foo"),
+			},
+		},
 		"file": {
 			{
 				`file("hello.txt")`,
diff --git a/website/docs/language/functions/ephemeralasnull.mdx b/website/docs/language/functions/ephemeralasnull.mdx
new file mode 100644
index 0000000000..f4df0a91ce
--- /dev/null
+++ b/website/docs/language/functions/ephemeralasnull.mdx
@@ -0,0 +1,30 @@
+---
+sidebar_label: ephemeralasnull
+description: The ephemeral as null function replaces all ephemeral values within the given object with null.
+---
+
+# `ephemeralasnull` Function
+
+`ephemeralasnull` takes any value and returns a copy of it with any ephemeral values replaced with null.  Ephemeral
+values can come from variables and outputs marked as ephemeral, as well as ephemeral resources.
+
+## Examples
+
+```hcl
+> ephemeralasnull("Hello World")
+"Hello World"
+> ephemeralasnull(var.ephemeral_variable)
+null
+> ephemeralasnull(ephemeral.some_resource)
+null
+> ephemeralasnull([4, var.ephemeral_variable])
+[4, null]
+> ephemeralasnull({
+  "field": "value",
+  "ephemeral": var.ephemeral_variable,
+})
+{
+  "field": "value",
+  "ephemeral": null,
+}
+```