diff --git a/backend/spec/api.md b/backend/spec/api.md
index 20f055b..c2dc893 100644
--- a/backend/spec/api.md
+++ b/backend/spec/api.md
@@ -27,6 +27,19 @@ Notes:
 - Adds CORS middleware based on `origins`
 - Calls `axum::serve` with a listener
 
+--- Plan routes
+
+## `async fn list_plans(...) -> Response`
+
+- Serves `GET /plans`
+- Return `data` is a list of plan structs from `Repo::list_plans`
+
+## `async fn get_plan(...) -> Response`
+
+- Serves `GET /plans/:id`
+- Return `data` is a single plan struct matching `id`
+- If plan does not exist, return `404` with `code=not-found`
+
 --- Tenant routes
 
 ## `async fn list_tenants(...) -> Response`
@@ -100,6 +113,13 @@ Notes:
 - If user is a tenant, `tenant` query parameter is not ok; authenticated `pubkey` is used
 - Return `data` is a list of invoice structs from `repo.list_invoices`
 
+## `async fn update_tenant_billing(...) -> Response`
+
+- Serves `PUT /tenants/:pubkey/billing`
+- Authorizes admin or matching tenant
+- Updates tenant billing NWC URL using `repo.update_tenant_nwc_url`
+- Return `data` is the submitted billing payload
+
 # Utility functions
 
 ## `extract_auth_pubkey(headers: &HeaderMap, method: &Method, uri: &Uri) -> Result<String>`
diff --git a/backend/spec/models.md b/backend/spec/models.md
index b561840..d143311 100644
--- a/backend/spec/models.md
+++ b/backend/spec/models.md
@@ -27,6 +27,23 @@ Activity is an audit log of all actions performed by a user or a worker process.
 - `resource_type` is a string identifying the resource type being modified.
 - `resource_id` is a string identifying the resource id being modified.
 
+# Plan
+
+A plan represents a rate charged for relays at a given feature/usage limit. Plans aren't saved to the database, but are simply hardcoded. However, they are exposed through the API so they can be used as a single source of truth.
+
+- `id` - the plan slug
+- `name` - the plan name
+- `sats` - the plan't cost per month
+- `members` - the max number of members a relay can have before needing to upgrade. If empty, membership is not limited.
+- `blossom` - whether blossom media hosting is available on this plan
+- `livekit` - whether livekit audio/video calls are available on this plan
+
+There are three plans available:
+
+- `free` - 0 sats/mo, up to 10 members, no blossom/livekit
+- `basic` - 10k sats/mo, up to 100 members, includes blossom/livekit
+- `growth` - 50k sats/mo, unlimited members, includes blossom/livekit
+
 # Tenant
 
 Tenants are customers of the service, identified by a nostr `pubkey`. Public metadata like name etc are pulled from the nostr network. They also have associated billing information.
diff --git a/backend/spec/repo.md b/backend/spec/repo.md
index e2a3d85..e3a9bb8 100644
--- a/backend/spec/repo.md
+++ b/backend/spec/repo.md
@@ -48,6 +48,11 @@ Notes:
 - Updates tenant `nwc_url`
 - Logs activity as `(update_tenant_nwc_url, tenant_id)`
 
+## `pub fn list_plans() -> Vec<Plan>`
+
+- Returns the hardcoded relay plans used by the system (`free`, `basic`, `growth`)
+- This is the source of truth for plan metadata exposed via API
+
 ## `pub fn list_relays(&self, tenant_id: Option<&str>) -> Result<Vec<Relay>>`
 
 - Returns all matching relays
@@ -120,3 +125,8 @@ Notes:
 ## `pub fn list_activity(&self, since: &i64, tenant: Option<&str>) -> Result<Vec<Activity>>`
 
 - Returns all activity occuring after `since` matching `tenant`
+
+## `pub fn get_relay_plan_sats(&self, plan: &str) -> Result<i64>`
+
+- Returns the monthly sats amount for a given plan id
+- Uses `list_plans()` data for consistent pricing logic across API and billing
diff --git a/backend/src/api.rs b/backend/src/api.rs
index f039dd2..ede24d4 100644
--- a/backend/src/api.rs
+++ b/backend/src/api.rs
@@ -76,6 +76,8 @@ impl Api {
         };
 
         let app = Router::new()
+            .route("/plans", get(list_plans))
+            .route("/plans/:id", get(get_plan))
             .route("/tenants", get(list_tenants).post(create_tenant))
             .route("/tenants/:pubkey", get(get_tenant))
             .route("/tenants/:pubkey/billing", put(update_tenant_billing))
@@ -323,6 +325,36 @@ async fn list_tenants(
     }
 }
 
+async fn list_plans(
+    State(state): State<AppState>,
+    headers: HeaderMap,
+    method: Method,
+    uri: Uri,
+) -> Response {
+    if let Err(e) = extract_auth_pubkey(&headers, &method, &uri, &state.api.host) {
+        return auth_fail_response(e);
+    }
+
+    ok(StatusCode::OK, Repo::list_plans())
+}
+
+async fn get_plan(
+    State(state): State<AppState>,
+    headers: HeaderMap,
+    method: Method,
+    uri: Uri,
+    Path(id): Path<String>,
+) -> Response {
+    if let Err(e) = extract_auth_pubkey(&headers, &method, &uri, &state.api.host) {
+        return auth_fail_response(e);
+    }
+
+    match Repo::list_plans().into_iter().find(|p| p.id == id) {
+        Some(plan) => ok(StatusCode::OK, plan),
+        None => err(StatusCode::NOT_FOUND, "not-found", "plan not found"),
+    }
+}
+
 async fn get_tenant(
     State(state): State<AppState>,
     headers: HeaderMap,
diff --git a/backend/src/billing.rs b/backend/src/billing.rs
index cdda2af..78124c5 100644
--- a/backend/src/billing.rs
+++ b/backend/src/billing.rs
@@ -125,7 +125,7 @@ impl Billing {
             if hours <= 0 {
                 continue;
             }
-            let plan_monthly = self.repo.get_relay_plan_amount_sats(&relay.plan).await?;
+            let plan_monthly = self.repo.get_relay_plan_sats(&relay.plan).await?;
             if plan_monthly <= 0 {
                 continue;
             }
@@ -228,7 +228,7 @@ impl Billing {
         Ok(())
     }
 
-    async fn make_bolt11(&self, amount_sats: i64) -> Result<String> {
+    async fn make_bolt11(&self, sats: i64) -> Result<String> {
         if self.nwc_url.trim().is_empty() {
             anyhow::bail!("NWC_URL not configured")
         }
@@ -236,7 +236,7 @@ impl Billing {
         let uri = nostr_sdk::nips::nip47::NostrWalletConnectURI::parse(&self.nwc_url)?;
         let req = nostr_sdk::nips::nip47::Request::make_invoice(
             nostr_sdk::nips::nip47::MakeInvoiceRequest {
-                amount: (amount_sats as u64) * 1_000,
+                amount: (sats as u64) * 1_000,
                 description: Some("Caravel relay invoice".to_string()),
                 description_hash: None,
                 expiry: None,
diff --git a/backend/src/models.rs b/backend/src/models.rs
index 34c2e94..35709b5 100644
--- a/backend/src/models.rs
+++ b/backend/src/models.rs
@@ -10,6 +10,16 @@ pub struct Activity {
     pub resource_id: String,
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Plan {
+    pub id: String,
+    pub name: String,
+    pub sats: i64,
+    pub members: Option<i64>,
+    pub blossom: bool,
+    pub livekit: bool,
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
 pub struct Tenant {
     pub pubkey: String,
diff --git a/backend/src/repo.rs b/backend/src/repo.rs
index 8173568..935585f 100644
--- a/backend/src/repo.rs
+++ b/backend/src/repo.rs
@@ -7,7 +7,7 @@ use sqlx::{
     sqlite::{SqliteConnectOptions, SqlitePoolOptions},
 };
 
-use crate::models::{Activity, Invoice, InvoiceItem, Relay, Tenant};
+use crate::models::{Activity, Invoice, InvoiceItem, Plan, Relay, Tenant};
 
 #[derive(Clone)]
 pub struct Repo {
@@ -502,15 +502,43 @@ impl Repo {
         Ok(count)
     }
 
-    pub async fn get_relay_plan_amount_sats(&self, plan: &str) -> Result<i64> {
-        let sats = match plan {
-            "free" => 0,
-            "basic" => 10_000,
-            "growth" => 50_000,
-            _ => 0,
-        };
+    pub async fn get_relay_plan_sats(&self, plan: &str) -> Result<i64> {
+        let sats = Self::list_plans()
+            .into_iter()
+            .find(|p| p.id == plan)
+            .map(|p| p.sats)
+            .unwrap_or(0);
         Ok(sats)
     }
+
+    pub fn list_plans() -> Vec<Plan> {
+        vec![
+            Plan {
+                id: "free".to_string(),
+                name: "Free".to_string(),
+                sats: 0,
+                members: Some(10),
+                blossom: false,
+                livekit: false,
+            },
+            Plan {
+                id: "basic".to_string(),
+                name: "Basic".to_string(),
+                sats: 10_000,
+                members: Some(100),
+                blossom: true,
+                livekit: true,
+            },
+            Plan {
+                id: "growth".to_string(),
+                name: "Growth".to_string(),
+                sats: 50_000,
+                members: None,
+                blossom: true,
+                livekit: true,
+            },
+        ]
+    }
 }
 
 fn normalize_sqlite_url(url: &str) -> String {