diff --git a/plugins/cri/images/plugin.go b/plugins/cri/images/plugin.go
index 844fe74398..9fd7051291 100644
--- a/plugins/cri/images/plugin.go
+++ b/plugins/cri/images/plugin.go
@@ -209,22 +209,22 @@ func migrateConfig(dst, src map[string]interface{}) {
 	}
 
 	var runtimePlatforms map[string]interface{}
-	if v, ok := dst["runtime_platform"]; ok {
+	if v, ok := dst["runtime_platforms"]; ok {
 		runtimePlatforms = v.(map[string]interface{})
 	} else {
 		runtimePlatforms = map[string]interface{}{}
 	}
 	for runtime, v := range runtimesConf.(map[string]interface{}) {
 		runtimeConf := v.(map[string]interface{})
-		if snapshotter, ok := runtimeConf["snapshot"]; ok && snapshotter != "" {
+		if snapshotter, ok := runtimeConf["snapshotter"]; ok && snapshotter != "" {
 			runtimePlatforms[runtime] = map[string]interface{}{
-				"platform":    platforms.DefaultStrict(),
+				"platform":    platforms.DefaultString(),
 				"snapshotter": snapshotter,
 			}
 		}
 	}
 	if len(runtimePlatforms) > 0 {
-		dst["runtime_platform"] = runtimePlatforms
+		dst["runtime_platforms"] = runtimePlatforms
 	}
 
 	for _, key := range []string{
diff --git a/plugins/cri/images/plugin_test.go b/plugins/cri/images/plugin_test.go
index 7e9f0d7ede..a7c14795f9 100644
--- a/plugins/cri/images/plugin_test.go
+++ b/plugins/cri/images/plugin_test.go
@@ -20,9 +20,11 @@ import (
 	"context"
 	"testing"
 
-	"github.com/containerd/containerd/v2/plugins"
+	"github.com/containerd/platforms"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/containerd/containerd/v2/plugins"
 )
 
 func TestSandboxImageConfigMigration(t *testing.T) {
@@ -68,3 +70,42 @@ func TestRegistryConfigMigration(t *testing.T) {
 	configPath := v.(string)
 	assert.Equal(t, path, configPath)
 }
+
+func TestRuntimePlatformsConfigMigration(t *testing.T) {
+	snapshotter := "devmapper"
+	grpcCri := map[string]any{
+		"containerd": map[string]any{
+			"runtimes": map[string]any{
+				"kata": map[string]any{
+					// Old per-runtime snapshotter key is "snapshotter", not "snapshot".
+					"snapshotter": snapshotter,
+				},
+				// Runtime with no snapshotter should not appear in runtime_platforms.
+				"runc": map[string]any{},
+			},
+		},
+	}
+	pluginConfigs := map[string]any{
+		string(plugins.GRPCPlugin) + ".cri": grpcCri,
+	}
+	configMigration(context.Background(), 2, pluginConfigs)
+
+	v, ok := pluginConfigs[string(plugins.CRIServicePlugin)+".images"]
+	require.True(t, ok)
+	images := v.(map[string]any)
+
+	// The destination key is "runtime_platforms" (plural), matching the TOML
+	// tag on ImageConfig.RuntimePlatforms.
+	v, ok = images["runtime_platforms"]
+	require.True(t, ok, "runtime_platforms key must be present after migration")
+	runtimePlatforms := v.(map[string]any)
+
+	kata, ok := runtimePlatforms["kata"]
+	require.True(t, ok, "kata runtime must be present in runtime_platforms")
+	kataConf := kata.(map[string]any)
+	assert.Equal(t, platforms.DefaultString(), kataConf["platform"])
+	assert.Equal(t, snapshotter, kataConf["snapshotter"])
+
+	_, ok = runtimePlatforms["runc"]
+	assert.False(t, ok, "runc has no snapshotter and must not appear in runtime_platforms")
+}