diff --git a/src/blindpay/resources/customers/customers.py b/src/blindpay/resources/customers/customers.py
index 7456877..1f8c9b2 100644
--- a/src/blindpay/resources/customers/customers.py
+++ b/src/blindpay/resources/customers/customers.py
@@ -252,7 +252,7 @@
     "1000000_9999999",
     "10000000_49999999",
     "50000000_249999999",
-    "2500000000_plus",
+    "250000000_plus",
 ]
 
 SourceOfWealth = Literal[
diff --git a/tests/test_types.py b/tests/test_types.py
index 57e4219..b2f75fd 100644
--- a/tests/test_types.py
+++ b/tests/test_types.py
@@ -6,6 +6,7 @@
 """
 
 from blindpay.resources.custodial_wallets.custodial_wallets import CreateCustodialWalletInput
+from blindpay.resources.customers.customers import EstimatedAnnualRevenue
 from blindpay.resources.payins.payins import BankDetails, CreateEvmPayinResponse, GetPayinTrackResponse, Payin
 from blindpay.types import BankAccountType, PaginationMetadata
 
@@ -254,3 +255,12 @@ def test_external_id_is_optional(self):
             "external_id": "your-database-id",
         }
         assert with_external_id.get("external_id") == "your-database-id"
+
+
+class TestEstimatedAnnualRevenueTopBandIsCorrect:
+    def test_250_million_plus_is_a_valid_value(self):
+        # The band below tops out at 249999999, so 250000000_plus is the only
+        # coherent top band; the old "2500000000_plus" (2.5 billion, an extra
+        # zero) is a value the API rejects.
+        value: EstimatedAnnualRevenue = "250000000_plus"
+        assert value == "250000000_plus"