diff --git a/crates/api_models/src/admin.rs b/crates/api_models/src/admin.rs
index a1b13c5ff315..6162ceffcb30 100644
--- a/crates/api_models/src/admin.rs
+++ b/crates/api_models/src/admin.rs
@@ -265,7 +265,7 @@ pub struct MerchantAccountResponse {
     pub intent_fulfillment_time: Option<i64>,
 
     /// The organization id merchant is associated with
-    pub organization_id: Option<String>,
+    pub organization_id: String,
 
     ///  A boolean value to indicate if the merchant has recon service is enabled or not, by default value is false
     pub is_recon_enabled: bool,
diff --git a/crates/diesel_models/src/merchant_account.rs b/crates/diesel_models/src/merchant_account.rs
index 2b63d4bf9b2b..dd68f3755f11 100644
--- a/crates/diesel_models/src/merchant_account.rs
+++ b/crates/diesel_models/src/merchant_account.rs
@@ -36,7 +36,7 @@ pub struct MerchantAccount {
     pub modified_at: time::PrimitiveDateTime,
     pub frm_routing_algorithm: Option<serde_json::Value>,
     pub payout_routing_algorithm: Option<serde_json::Value>,
-    pub organization_id: Option<String>,
+    pub organization_id: String,
     pub is_recon_enabled: bool,
     pub default_profile: Option<String>,
     pub recon_status: storage_enums::ReconStatus,
@@ -65,7 +65,7 @@ pub struct MerchantAccountNew {
     pub modified_at: time::PrimitiveDateTime,
     pub frm_routing_algorithm: Option<serde_json::Value>,
     pub payout_routing_algorithm: Option<serde_json::Value>,
-    pub organization_id: Option<String>,
+    pub organization_id: String,
     pub is_recon_enabled: bool,
     pub default_profile: Option<String>,
     pub recon_status: storage_enums::ReconStatus,
diff --git a/crates/diesel_models/src/schema.rs b/crates/diesel_models/src/schema.rs
index d8a888046b99..0da819f2a70c 100644
--- a/crates/diesel_models/src/schema.rs
+++ b/crates/diesel_models/src/schema.rs
@@ -437,7 +437,7 @@ diesel::table! {
         frm_routing_algorithm -> Nullable<Jsonb>,
         payout_routing_algorithm -> Nullable<Jsonb>,
         #[max_length = 32]
-        organization_id -> Nullable<Varchar>,
+        organization_id -> Varchar,
         is_recon_enabled -> Bool,
         #[max_length = 64]
         default_profile -> Nullable<Varchar>,
diff --git a/crates/router/src/core/admin.rs b/crates/router/src/core/admin.rs
index c7009bf4cc98..ec229bd8a564 100644
--- a/crates/router/src/core/admin.rs
+++ b/crates/router/src/core/admin.rs
@@ -31,6 +31,8 @@ use crate::{
     utils::{self, OptionExt},
 };
 
+const DEFAULT_ORG_ID: &str = "org_abcdefghijklmn";
+
 #[inline]
 pub fn create_merchant_publishable_key() -> String {
     format!(
@@ -164,7 +166,7 @@ pub async fn create_merchant_account(
             intent_fulfillment_time: req.intent_fulfillment_time.map(i64::from),
             payout_routing_algorithm: req.payout_routing_algorithm,
             id: None,
-            organization_id: req.organization_id,
+            organization_id: req.organization_id.unwrap_or(DEFAULT_ORG_ID.to_string()),
             is_recon_enabled: false,
             default_profile: None,
             recon_status: diesel_models::enums::ReconStatus::NotRequested,
diff --git a/crates/router/src/types/domain/merchant_account.rs b/crates/router/src/types/domain/merchant_account.rs
index 30950f8c9c99..c32942a847da 100644
--- a/crates/router/src/types/domain/merchant_account.rs
+++ b/crates/router/src/types/domain/merchant_account.rs
@@ -40,7 +40,7 @@ pub struct MerchantAccount {
     pub modified_at: time::PrimitiveDateTime,
     pub intent_fulfillment_time: Option<i64>,
     pub payout_routing_algorithm: Option<serde_json::Value>,
-    pub organization_id: Option<String>,
+    pub organization_id: String,
     pub is_recon_enabled: bool,
     pub default_profile: Option<String>,
     pub recon_status: diesel_models::enums::ReconStatus,
diff --git a/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/down.sql b/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/down.sql
new file mode 100644
index 000000000000..eb6a02e3dac0
--- /dev/null
+++ b/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/down.sql
@@ -0,0 +1,3 @@
+-- This file should undo anything in `up.sql`
+ALTER TABLE merchant_account
+ALTER COLUMN organization_id DROP NOT NULL;
diff --git a/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/up.sql b/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/up.sql
new file mode 100644
index 000000000000..eb6b24e16aeb
--- /dev/null
+++ b/migrations/2023-10-05-085859_make_org_id_mandatory_in_ma/up.sql
@@ -0,0 +1,8 @@
+-- Your SQL goes here
+UPDATE merchant_account
+SET organization_id = 'org_abcdefghijklmn'
+WHERE organization_id IS NULL;
+
+ALTER TABLE merchant_account
+ALTER COLUMN organization_id
+SET NOT NULL;
diff --git a/openapi/openapi_spec.json b/openapi/openapi_spec.json
index 13ddad32af58..56632a68c39b 100644
--- a/openapi/openapi_spec.json
+++ b/openapi/openapi_spec.json
@@ -6113,6 +6113,7 @@
           "enable_payment_response_hash",
           "redirect_to_merchant_with_http_post",
           "primary_business_details",
+          "organization_id",
           "is_recon_enabled",
           "recon_status"
         ],
@@ -6241,8 +6242,7 @@
           },
           "organization_id": {
             "type": "string",
-            "description": "The organization id merchant is associated with",
-            "nullable": true
+            "description": "The organization id merchant is associated with"
           },
           "is_recon_enabled": {
             "type": "boolean",