WooCommerce Memberships: data model and Subscriptions link

Use this when an integration needs exact storage names. Prefer Memberships public APIs and objects for writes; use these keys for audits, migrations, import/export mapping, and low-level debugging.

Core storage

Entity	Storage	Name/key	Notes
Membership plan	CPT	wc_membership_plan	Registered by WC_Memberships_Post_Types. Not public, UI under WooCommerce when possible.
User membership	CPT	wc_user_membership	One post per user-plan membership. Not public.
Plan relation	WP post field	wc_user_membership.post_parent	This is the plan ID. Do not invent _member_plan_id; the installed plugin uses post_parent.
Member relation	WP post field	wc_user_membership.post_author	This is the member/user ID.
Subscription	WC order type	shop_subscription	From WooCommerce Subscriptions; use wcs_get_subscription().
Membership rules	Option	wc_memberships_rules	Stores serialized rule arrays for all plans. Rules are not CPTs.
Profile field definitions	Option	wc_memberships_profile_fields	Definition data keyed by profile field slug.
Profile field values	User meta	_wc_memberships_profile_field_{slug}	Stored by Profile_Field\User_Meta.
Order grant marker	WC order meta	_wc_memberships_access_granted	Array keyed by user membership ID, with already_granted, granting_order_status, and related details.

Membership statuses

WP post statuses use the wcm- prefix. Object methods usually accept/return unprefixed slugs.

WP status	Object status	Meaning
wcm-active	active	Active access.
wcm-delayed	delayed	Membership exists but access starts later.
wcm-complimentary	complimentary	Admin/complimentary access.
wcm-free_trial	free_trial	Added by the Subscriptions integration when a linked subscription is in trial.
wcm-paused	paused	Paused membership.
wcm-expired	expired	Expired membership.
wcm-cancelled	cancelled	Cancelled membership.

Use wc_memberships_get_user_membership_statuses() for the installed status catalog and wc_memberships()->get_user_memberships_instance()->get_active_access_membership_statuses() for statuses that grant access.

Membership plan meta

These keys are stored on wc_membership_plan posts and exposed by WC_Memberships_Membership_Plan::get_meta_keys().

Meta key	Purpose
_access_method	manual-only, signup, or purchase access method.
_access_length	Access length value, e.g. unlimited, specific, fixed, or an amount/period value depending on method.
_access_start_date	Fixed access start datetime.
_access_end_date	Fixed access end datetime.
_product_ids	Product or variation IDs that grant access.
_members_area_sections	Enabled members-area sections.
_email_content	Plan-specific email content settings.

Use plan methods such as get_access_method(), set_access_method(), get_product_ids(), set_product_ids(), get_access_start_date(), and get_access_end_date() rather than direct meta writes.

User membership meta

These keys are stored on wc_user_membership posts and exposed by WC_Memberships_User_Membership::get_meta_keys().

Meta key	Purpose
_start_date	Membership start datetime.
_end_date	Membership end datetime. Empty/unset can mean unlimited.
_cancelled_date	Cancellation datetime.
_paused_date	Current pause start datetime.
_paused_intervals	Historical paused intervals.
_product_id	Product or variation ID that granted access.
_order_id	Order ID that granted access.
_previous_owners	Previous owner user IDs after transfers.
_renewal_login_token	Auto-login token used for renewal flows.
_locked	Operation lock for race-sensitive flows.

Use wc_memberships_create_user_membership(), wc_memberships_get_user_membership(), and WC_Memberships_User_Membership methods for writes and lifecycle side effects.

Rule storage

Rules are stored in the wc_memberships_rules option, not as posts. Rule type values:

Rule type	Purpose	Important fields
content_restriction	Restricts posts, pages, CPTs, or terms.	content_type, content_type_name, object_ids, access_schedule, access_schedule_exclude_trial.
product_restriction	Restricts product viewing or purchase.	Same fields plus access_type (view or purchase).
purchasing_discount	Applies member discounts.	discount_type, discount_amount, active.

Common rule fields are id, membership_plan_id, active, rule_type, content_type, content_type_name, object_ids, discount_type, discount_amount, access_type, access_schedule, access_schedule_exclude_trial, and meta_data.

Use wc_memberships()->get_rules_instance()->get_rules(), get_plan_rules(), add_rules(), update_rules(), or delete_rules() instead of editing the option directly.

Memberships to Subscriptions relation

WooCommerce Memberships links to WooCommerce Subscriptions by adding extra meta to the wc_user_membership post. The subscription itself is still a WCS shop_subscription.

User membership meta	Purpose
_subscription_id	Linked shop_subscription ID. This is the primary relation key from membership to subscription.
_has_installment_plan	Flag/value used when the linked subscription is treated as an installment plan. The code stores the subscription ID when it auto-detects the flag.
_free_trial_end_date	Trial end datetime mirrored from the linked subscription trial.

Public helpers:

$integration = wc_memberships()->get_integrations_instance()->get_subscriptions_instance();
$subscription = $integration ? $integration->get_subscription_from_membership( $user_membership ) : null;
$memberships = $integration ? $integration->get_memberships_from_subscription( $subscription ) : array();

$is_linked = wc_memberships_is_user_membership_linked_to_subscription( $user_membership );

Do not assume a reverse meta key on the subscription. Reverse lookup queries wc_user_membership posts with _subscription_id = {subscription_id}.

Subscription-linked lifecycle

When Subscriptions is active, Memberships may return WC_Memberships_Integration_Subscriptions_User_Membership for linked memberships.

Important behavior:

• Linking calls WC_Memberships_Integration_Subscriptions_User_Membership::set_subscription_id() and fires wc_memberships_user_membership_linked_to_subscription.
• Unlinking deletes _subscription_id and fires wc_memberships_user_membership_unlinked_from_subscription.
• Subscription trial dates can set membership status to free_trial and write _free_trial_end_date.
• Subscription date/status changes can update linked membership dates/statuses.
• If a plan is granted by subscription products, Memberships checks whether the subscription product grants the plan and may keep access tied to subscription activity.
• Installment plan behavior differs: completion can unlink the subscription while keeping membership access according to the plan rules.

Gifting and Memberships

WooCommerce Subscriptions Gifting changes who receives membership access when the gifted subscription product grants a Memberships plan.

Storage bridge:

• Gifted subscription stores recipient user on subscription meta _recipient_user after recipient account resolution.
• Parent order item stores wcsg_recipient = wcsg_recipient_id_{user_id}.
• Memberships grant filtering uses wcsg_recipient to grant access to recipient users instead of the purchaser for gifted items.
• The membership still stores the linked subscription in _subscription_id.

If an order has the same membership-granting product for several recipients, do not pick the first subscription in the order. Use the WCSG/Memberships integration logic or query recipient subscriptions before assigning _subscription_id.

Safe query patterns

// Memberships for a subscription.
$memberships = get_posts( array(
    'post_type'      => 'wc_user_membership',
    'post_status'    => wc_memberships_get_user_membership_statuses( false ),
    'fields'         => 'ids',
    'posts_per_page' => -1,
    'meta_query'     => array(
        array(
            'key'   => '_subscription_id',
            'value' => $subscription_id,
        ),
    ),
) );

// Prefer API for normal code.
$user_membership = wc_memberships_get_user_membership( $user_id, $plan_id );

Common mistakes

// WRONG: this key is not the plan relation in the installed plugin.
$plan_id = get_post_meta( $membership_id, '_member_plan_id', true );

// RIGHT: use the object or post_parent.
$membership = wc_memberships_get_user_membership( $membership_id );
$plan_id = $membership ? $membership->get_plan_id() : 0;

// WRONG: raw post status write misses Memberships side effects.
wp_update_post( array( 'ID' => $membership_id, 'post_status' => 'wcm-active' ) );

// RIGHT: use object status API with unprefixed status.
$membership->update_status( 'active' );

Cross-references

• Use wcm-membership-hooks for lifecycle hooks and REST/webhook extension points.
• Use wcm-access-discounts for access checks, restrictions, drip timing, and member discounts.
• Use wcs-data-model-switching-gifting for Subscriptions order type, subscription meta, switch data, and gifting data.