diff --git a/frontend/cache.go b/frontend/cache.go
index 21c4ccf97..6fdb75383 100644
--- a/frontend/cache.go
+++ b/frontend/cache.go
@@ -3,16 +3,21 @@ package main
 // Copyright (c) Microsoft Corporation.
 // Licensed under the Apache License 2.0.
 
-import "github.com/Azure/ARO-HCP/internal/api"
+import (
+	"github.com/Azure/ARO-HCP/internal/api"
+	"github.com/Azure/ARO-HCP/internal/api/subscription"
+)
 
 type cache struct {
-	cluster map[string]*api.HCPOpenShiftCluster
+	cluster      map[string]*api.HCPOpenShiftCluster
+	subscription map[string]*subscription.Subscription
 }
 
 // NewCache returns a new cache.
 func NewCache() *cache {
 	return &cache{
-		cluster: make(map[string]*api.HCPOpenShiftCluster),
+		cluster:      make(map[string]*api.HCPOpenShiftCluster),
+		subscription: make(map[string]*subscription.Subscription),
 	}
 }
 
@@ -28,3 +33,16 @@ func (c *cache) SetCluster(id string, cluster *api.HCPOpenShiftCluster) {
 func (c *cache) DeleteCluster(id string) {
 	delete(c.cluster, id)
 }
+
+func (c *cache) GetSubscription(id string) (*subscription.Subscription, bool) {
+	subscription, found := c.subscription[id]
+	return subscription, found
+}
+
+func (c *cache) SetSubscription(id string, subscription *subscription.Subscription) {
+	c.subscription[id] = subscription
+}
+
+func (c *cache) DeleteSubscription(id string) {
+	delete(c.subscription, id)
+}
diff --git a/frontend/frontend.go b/frontend/frontend.go
index 3392a294e..ae4b048c7 100644
--- a/frontend/frontend.go
+++ b/frontend/frontend.go
@@ -17,6 +17,7 @@ import (
 
 	"github.com/Azure/ARO-HCP/internal/api"
 	"github.com/Azure/ARO-HCP/internal/api/arm"
+	"github.com/Azure/ARO-HCP/internal/api/subscription"
 )
 
 const (
@@ -97,6 +98,7 @@ func NewFrontend(logger *slog.Logger, listener net.Listener) *Frontend {
 	mux.Handle(
 		MuxPattern(http.MethodPost, PatternSubscriptions, PatternResourceGroups, PatternProviders, PatternResourceName, PatternActionName),
 		postMuxMiddleware.HandlerFunc(f.ArmResourceAction))
+	mux.Handle(MuxPattern(http.MethodPut, PatternSubscriptions), postMuxMiddleware.HandlerFunc(f.ArmSubscriptionAction))
 	f.server.Handler = mux
 
 	return f
@@ -277,3 +279,33 @@ func (f *Frontend) ArmResourceAction(writer http.ResponseWriter, request *http.R
 
 	writer.WriteHeader(http.StatusOK)
 }
+
+func (f *Frontend) ArmSubscriptionAction(writer http.ResponseWriter, request *http.Request) {
+	ctx := request.Context()
+	logger := ctx.Value(ContextKeyLogger).(*slog.Logger)
+	versionedInterface := ctx.Value(ContextKeyVersion).(api.Version)
+	logger.Info(fmt.Sprintf("%s: ArmSubscriptionAction", versionedInterface))
+
+	body := ctx.Value(ContextKeyBody).([]byte)
+	var subscription subscription.Subscription
+	err := json.Unmarshal(body, &subscription)
+	if err != nil {
+		f.logger.Error(err.Error())
+		writer.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	subId := request.PathValue(strings.ToLower(PathSegmentSubscriptionID))
+	f.cache.SetSubscription(subId, &subscription)
+
+	resp, err := json.Marshal(subscription)
+	if err != nil {
+		f.logger.Error(err.Error())
+		writer.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	_, err = writer.Write(resp)
+	if err != nil {
+		f.logger.Error(err.Error())
+	}
+}
diff --git a/internal/api/subscription/register.go b/internal/api/subscription/register.go
new file mode 100644
index 000000000..e51cc7a82
--- /dev/null
+++ b/internal/api/subscription/register.go
@@ -0,0 +1,29 @@
+package subscription
+
+// Copyright (c) Microsoft Corporation.
+// Licensed under the Apache License 2.0.
+
+import (
+	"github.com/Azure/ARO-HCP/internal/api"
+)
+
+type version struct{}
+
+// NewHCPOpenShiftCluster implements api.Version.
+func (v version) NewHCPOpenShiftCluster(*api.HCPOpenShiftCluster) api.VersionedHCPOpenShiftCluster {
+	panic("'System Version 2.0' is not supported for HCP Cluster objects")
+}
+
+// UnmarshalHCPOpenShiftCluster implements api.Version.
+func (v version) UnmarshalHCPOpenShiftCluster([]byte, bool, *api.HCPOpenShiftCluster) error {
+	panic("'System Version 2.0' is not supported for HCP Cluster objects")
+}
+
+// String returns the api-version parameter value for this API.
+func (v version) String() string {
+	return "2.0"
+}
+
+func init() {
+	api.Register(version{})
+}
diff --git a/internal/api/subscription/subscription.go b/internal/api/subscription/subscription.go
new file mode 100644
index 000000000..dbec82341
--- /dev/null
+++ b/internal/api/subscription/subscription.go
@@ -0,0 +1,46 @@
+package subscription
+
+// Copyright (c) Microsoft Corporation.
+// Licensed under the Apache License 2.0.
+
+type Subscription struct {
+	State            RegistrationState `json:"state"`
+	RegsitrationDate *string           `json:"registrationDate,omitempty"`
+	Properties       *Properties       `json:"properties,omitempty"`
+}
+
+type Properties struct {
+	TenantId             *string              `json:"tenantId,omitempty"`
+	LocationPlacementId  *string              `json:"locationPlacementId,omitempty"`
+	QuotaId              *string              `json:"quotaId,omitempty"`
+	RegisteredFeatures   *[]Feature           `json:"registeredFeatures,omitempty"`
+	AvailabilityZones    *AvailabilityZone    `json:"availabilityZones,omitempty"`
+	SpendingLimit        *string              `json:"spendingLimit,omitempty"`
+	AccountOwner         *map[string]string   `json:"accountOwner,omitempty"`
+	ManagedByTenants     *[]map[string]string `json:"managedByTenants,omitempty"`
+	AdditionalProperties *map[string]string   `json:"additionalProperties,omitempty"`
+}
+
+type Feature struct {
+	Name  *string `json:"name,omitempty"`
+	State *string `json:"state,omitempty"`
+}
+
+type AvailabilityZone struct {
+	Location     *string        `json:"location,omitempty"`
+	ZoneMappings *[]ZoneMapping `json:"zoneMppings,omitempty"`
+}
+
+type ZoneMapping struct {
+	LogicalZone  *string `json:"logicalZone,omitempty"`
+	PhysicalZone *string `json:"physicalZone,omitempty"`
+}
+type RegistrationState string
+
+const (
+	Registered   RegistrationState = "Registered"
+	Unregistered RegistrationState = "Unregistered"
+	Warned       RegistrationState = "Warned"
+	Deleted      RegistrationState = "Deleted"
+	Suspended    RegistrationState = "Suspended"
+)