diff --git a/CHANGELOG.md b/CHANGELOG.md
index 94f0bbf6..35689be0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## Next Release
+
+- Removes the deprecated, unusable `add_credit_card` function
+  - Stripe has disabled the ability to pass plain credit card details over the wire and now requires using [Stripe.js/Elements/Checkout](https://support.stripe.com/questions/card-tokenization-restrictions-using-publishable-keys). Follow the [Decentralized (EasyPost-Manage Billing) Guide](https://docs.easypost.com/guides/get-started-with-forge/easypost-managed-billing-guide#referralcustomer-billing-management) for more details on the new flow to use.
+  - Makes `referral_customer.retrieve_easypost_stripe_api_key` public to help facilitate adding credit cards using Stripe.js
+
 ## v10.7.0 (2026-06-25)
 
 - Adds `params` to `request_pin` ensuring users can pass `easypost_details` to the call.
diff --git a/easypost/services/referral_customer_service.py b/easypost/services/referral_customer_service.py
index 17a3c533..236715ba 100644
--- a/easypost/services/referral_customer_service.py
+++ b/easypost/services/referral_customer_service.py
@@ -4,15 +4,10 @@
     Optional,
 )
 
-import requests
-
 from easypost.constant import (
     _FILTERS_KEY,
-    SEND_STRIPE_DETAILS_ERROR,
-    TIMEOUT,
 )
 from easypost.easypost_object import convert_to_easypost_object
-from easypost.errors import ExternalApiError
 from easypost.models import User
 from easypost.requestor import (
     RequestMethod,
@@ -95,40 +90,6 @@ def get_next_page(
 
         return self.all(**params)
 
-    def add_credit_card(
-        self,
-        referral_api_key: str,
-        number: str,
-        expiration_month: int,
-        expiration_year: int,
-        cvc: str,
-        priority: str = "primary",
-    ) -> dict[str, Any]:
-        """Add a credit card to EasyPost for a ReferralCustomer without needing a Stripe account.
-
-        This function requires the ReferralCustomer User's API key.
-        """
-        easypost_stripe_api_key = self._retrieve_easypost_stripe_api_key()
-
-        try:
-            stripe_token = self._create_stripe_token(
-                number,
-                expiration_month,
-                expiration_year,
-                cvc,
-                easypost_stripe_api_key,
-            )
-        except Exception:
-            raise ExternalApiError(message=SEND_STRIPE_DETAILS_ERROR)
-
-        response = self._create_easypost_credit_card(
-            referral_api_key,
-            stripe_token.get("id", ""),
-            priority=priority,
-        )
-
-        return convert_to_easypost_object(response)
-
     def add_credit_card_from_stripe(
         self,
         referral_api_key: str,
@@ -187,7 +148,7 @@ def add_bank_account_from_stripe(
 
         return convert_to_easypost_object(response)
 
-    def _retrieve_easypost_stripe_api_key(self) -> str:
+    def retrieve_easypost_stripe_api_key(self) -> str:
         """Retrieve EasyPost's Stripe public API key."""
         public_key = Requestor(self._client).request(
             method=RequestMethod.GET,
@@ -195,65 +156,3 @@ def _retrieve_easypost_stripe_api_key(self) -> str:
         )
 
         return public_key.get("public_key", "")
-
-    def _create_stripe_token(
-        self,
-        number: str,
-        expiration_month: int,
-        expiration_year: int,
-        cvc: str,
-        easypost_stripe_key: str,
-    ) -> dict[str, Any]:
-        """Get credit card token from Stripe."""
-        headers = {
-            # This Stripe endpoint only accepts URL form encoded bodies
-            "Content-type": "application/x-www-form-urlencoded",
-        }
-
-        credit_card_dict = {
-            "card": {
-                "number": number,
-                "exp_month": expiration_month,
-                "exp_year": expiration_year,
-                "cvc": cvc,
-            }
-        }
-
-        form_encoded_params = Requestor.form_encode_params(credit_card_dict)
-        url = "https://api.stripe.com/v1/tokens"
-
-        stripe_response = requests.post(
-            url,
-            params=form_encoded_params,
-            headers=headers,
-            auth=requests.auth.HTTPBasicAuth(easypost_stripe_key, ""),
-            timeout=TIMEOUT,
-        )
-
-        return stripe_response.json()
-
-    def _create_easypost_credit_card(
-        self,
-        referral_api_key: str,
-        stripe_object_id: str,
-        priority: str = "primary",
-    ) -> dict[str, Any]:
-        """Submit Stripe credit card token to EasyPost."""
-        params = {
-            "credit_card": {
-                "stripe_object_id": stripe_object_id,
-                "priority": priority,
-            }
-        }
-
-        # Override the API key to use the referral's for this single request
-        referral_client = deepcopy(self._client)
-        referral_client.api_key = referral_api_key
-
-        response = Requestor(referral_client).request(
-            method=RequestMethod.POST,
-            params=params,
-            url="/credit_cards",
-        )
-
-        return response
diff --git a/justfile b/justfile
index 3f9a19da..69ed6a83 100644
--- a/justfile
+++ b/justfile
@@ -5,7 +5,7 @@ TEST_DIR := "tests"
 
 # Build the project for release
 build:
-    {{VIRTUAL_BIN}}/python -m build
+    uv build
 
 # Clean the project
 clean:
diff --git a/pyproject.toml b/pyproject.toml
index fbda4c02..c6dac99a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -27,7 +27,6 @@ classifiers = [
 dependencies = ["requests >= 2.4.3"]
 optional-dependencies = { dev = [
     "bandit == 1.8.*",
-    "build == 1.2.*",
     "mypy == 1.15.*",
     "pdoc == 15.*",
     "pytest == 8.*",
diff --git a/tests/cassettes/test_referral_customer_add_credit_card.yaml b/tests/cassettes/test_referral_customer_add_credit_card.yaml
deleted file mode 100644
index 117e8dc6..00000000
--- a/tests/cassettes/test_referral_customer_add_credit_card.yaml
+++ /dev/null
@@ -1,212 +0,0 @@
-interactions:
-- request:
-    body: null
-    headers:
-      Accept:
-      - '*/*'
-      Accept-Encoding:
-      - gzip, deflate
-      Connection:
-      - keep-alive
-      authorization:
-      - <REDACTED>
-      user-agent:
-      - <REDACTED>
-    method: GET
-    uri: https://api.easypost.com/v2/partners/stripe_public_key
-  response:
-    body:
-      string: '{"public_key": "pk_x3JSr5eOVWNTLRej8cZDde9VQ0AT5"}'
-    headers:
-      cache-control:
-      - private, no-cache, no-store
-      content-length:
-      - '49'
-      content-type:
-      - application/json; charset=utf-8
-      expires:
-      - '0'
-      pragma:
-      - no-cache
-      referrer-policy:
-      - strict-origin-when-cross-origin
-      strict-transport-security:
-      - max-age=31536000; includeSubDomains; preload
-      transfer-encoding:
-      - chunked
-      x-backend:
-      - easypost
-      x-content-type-options:
-      - nosniff
-      x-download-options:
-      - noopen
-      x-ep-request-uuid:
-      - 8e8eb62567c9fc1ae2b97b760018a860
-      x-frame-options:
-      - SAMEORIGIN
-      x-node:
-      - bigweb58nuq
-      x-permitted-cross-domain-policies:
-      - none
-      x-proxied:
-      - intlb4nuq 51d74985a2
-      - extlb1nuq 99aac35317
-      x-runtime:
-      - '0.022642'
-      x-version-label:
-      - easypost-202503061913-8f39069a2d-master
-      x-xss-protection:
-      - 1; mode=block
-    status:
-      code: 200
-      message: OK
-- request:
-    body: null
-    headers:
-      Accept:
-      - '*/*'
-      Accept-Encoding:
-      - gzip, deflate
-      Connection:
-      - keep-alive
-      Content-Length:
-      - '0'
-      Content-type:
-      - application/x-www-form-urlencoded
-      authorization:
-      - <REDACTED>
-      user-agent:
-      - <REDACTED>
-    method: POST
-    uri: https://api.stripe.com/v1/tokens?card%5Bexp_month%5D=05&card%5Bexp_year%5D=2028
-  response:
-    body:
-      string: '{"error": {"message": "This integration surface is unsupported for
-        publishable key tokenization. To enable this surface, please go to your dashboard
-        (https://dashboard.stripe.com/settings/integration). See https://support.stripe.com/questions/card-tokenization-restrictions-using-publishable-keys
-        for more details", "request_log_url": "https://dashboard.stripe.com/logs/req_h4qLymbw74w7cU?t=1741290522",
-        "type": "invalid_request_error"}}'
-    headers:
-      Access-Control-Allow-Credentials:
-      - 'true'
-      Access-Control-Allow-Methods:
-      - GET, HEAD, PUT, PATCH, POST, DELETE
-      Access-Control-Allow-Origin:
-      - '*'
-      Access-Control-Expose-Headers:
-      - Request-Id, Stripe-Manage-Version, Stripe-Should-Retry, X-Stripe-External-Auth-Required,
-        X-Stripe-Privileged-Session-Required
-      Access-Control-Max-Age:
-      - '300'
-      Cache-Control:
-      - no-cache, no-store
-      Connection:
-      - keep-alive
-      Content-Length:
-      - '458'
-      Content-Security-Policy:
-      - base-uri 'none'; default-src 'none'; form-action 'none'; frame-ancestors 'none';
-        img-src 'self'; script-src 'self' 'report-sample'; style-src 'self'; worker-src
-        'none'; upgrade-insecure-requests; report-uri https://q.stripe.com/csp-violation?q=0Vy5Ta2pFgzW2Ya4hl8lPGzkEN1C3IyDpB204-q3EAArRvHI8ALkzEjhMEmUL0t__fht0crtWzoPxzs_
-      Content-Type:
-      - application/json
-      Cross-Origin-Opener-Policy-Report-Only:
-      - same-origin; report-to="coop"
-      Date:
-      - Thu, 06 Mar 2025 19:48:42 GMT
-      Idempotency-Key:
-      - 4f8c8607-a9d0-4c8e-a5be-cd519b399771
-      Original-Request:
-      - req_h4qLymbw74w7cU
-      Report-To:
-      - '{"group":"coop","max_age":8640,"endpoints":[{"url":"https://q.stripe.com/coop-report"}],"include_subdomains":true}'
-      Reporting-Endpoints:
-      - coop="https://q.stripe.com/coop-report"
-      Request-Id:
-      - req_h4qLymbw74w7cU
-      Server:
-      - nginx
-      Strict-Transport-Security:
-      - max-age=63072000; includeSubDomains; preload
-      Stripe-Should-Retry:
-      - 'false'
-      Stripe-Version:
-      - '2020-08-27'
-      Vary:
-      - Origin
-      X-Stripe-Priority-Routing-Enabled:
-      - 'true'
-      X-Stripe-Routing-Context-Priority-Tier:
-      - livemode-critical
-      X-Wc:
-      - AB
-    status:
-      code: 400
-      message: Bad Request
-- request:
-    body: '{"credit_card": {"stripe_object_id": "", "priority": "primary"}}'
-    headers:
-      Accept:
-      - '*/*'
-      Accept-Encoding:
-      - gzip, deflate
-      Connection:
-      - keep-alive
-      Content-Length:
-      - '64'
-      Content-Type:
-      - application/json
-      authorization:
-      - <REDACTED>
-      user-agent:
-      - <REDACTED>
-    method: POST
-    uri: https://api.easypost.com/v2/credit_cards
-  response:
-    body:
-      string: '{"error": {"code": "BAD_REQUEST", "message": "One of payment_method_reference
-        or payment_method_id must be provided", "errors": []}}'
-    headers:
-      cache-control:
-      - private, no-cache, no-store
-      content-length:
-      - '126'
-      content-type:
-      - application/json; charset=utf-8
-      expires:
-      - '0'
-      pragma:
-      - no-cache
-      referrer-policy:
-      - strict-origin-when-cross-origin
-      strict-transport-security:
-      - max-age=31536000; includeSubDomains; preload
-      transfer-encoding:
-      - chunked
-      x-backend:
-      - easypost
-      x-content-type-options:
-      - nosniff
-      x-download-options:
-      - noopen
-      x-ep-request-uuid:
-      - 8e8eb62867c9fc1ae2b97b780018a8da
-      x-frame-options:
-      - SAMEORIGIN
-      x-node:
-      - bigweb57nuq
-      x-permitted-cross-domain-policies:
-      - none
-      x-proxied:
-      - intlb3nuq 51d74985a2
-      - extlb1nuq 99aac35317
-      x-runtime:
-      - '0.078448'
-      x-version-label:
-      - easypost-202503061913-8f39069a2d-master
-      x-xss-protection:
-      - 1; mode=block
-    status:
-      code: 400
-      message: Bad Request
-version: 1
diff --git a/tests/cassettes/test_referral_customer_retrieve_easypost_stripe_api_key.yaml b/tests/cassettes/test_referral_customer_retrieve_easypost_stripe_api_key.yaml
new file mode 100644
index 00000000..b1b060fa
--- /dev/null
+++ b/tests/cassettes/test_referral_customer_retrieve_easypost_stripe_api_key.yaml
@@ -0,0 +1,67 @@
+interactions:
+- request:
+    body: null
+    headers:
+      Accept:
+      - '*/*'
+      Accept-Encoding:
+      - gzip, deflate
+      Connection:
+      - keep-alive
+      authorization:
+      - <REDACTED>
+      user-agent:
+      - <REDACTED>
+    method: GET
+    uri: https://api.easypost.com/v2/partners/stripe_public_key
+  response:
+    body:
+      string: '{"public_key": "pk_x3JSr5eOVWNTLRej8cZDde9VQ0AT5"}'
+    headers:
+      cache-control:
+      - private, no-cache, no-store
+      content-length:
+      - '49'
+      content-type:
+      - application/json; charset=utf-8
+      easypost-api-version:
+      - '2015-01-01'
+      expires:
+      - '0'
+      pragma:
+      - no-cache
+      referrer-policy:
+      - strict-origin-when-cross-origin
+      strict-transport-security:
+      - max-age=31536000; includeSubDomains; preload
+      transfer-encoding:
+      - chunked
+      vary:
+      - EasyPost-Api-Version
+      x-backend:
+      - easypost
+      x-content-type-options:
+      - nosniff
+      x-download-options:
+      - noopen
+      x-ep-request-uuid:
+      - 91d0a0fa6ab4301ce2b97bb400af2fd1
+      x-frame-options:
+      - SAMEORIGIN
+      x-node:
+      - web103azw
+      x-permitted-cross-domain-policies:
+      - none
+      x-proxied:
+      - intlb3azw f29267e751
+      - extlb2azw 07fb4d8f06
+      x-runtime:
+      - '0.029468'
+      x-version-label:
+      - easypost-202609231716-41b3efb4ec-main
+      x-xss-protection:
+      - 1; mode=block
+    status:
+      code: 200
+      message: OK
+version: 1
diff --git a/tests/test_referral_customer.py b/tests/test_referral_customer.py
index d39b15f9..d7990b87 100644
--- a/tests/test_referral_customer.py
+++ b/tests/test_referral_customer.py
@@ -1,5 +1,4 @@
 import os
-from unittest.mock import patch
 
 import pytest
 
@@ -74,58 +73,6 @@ def test_referral_get_next_page(partner_user_prod_client, page_size):
             raise Exception(_TEST_FAILED_INTENTIONALLY_ERROR)
 
 
-@pytest.mark.skip("flow is deprecated, cannot easily be tested due to Stripe changes")
-# PyVCR is having troubles matching the body of the form-encoded data here, override the default
-@pytest.mark.vcr(
-    match_on=[
-        "headers",
-        "method",
-        "query",
-        "uri",
-    ]
-)
-def test_referral_customer_add_credit_card(partner_user_prod_client, credit_card_details):
-    """This test requires a partner customer's production API key via PARTNER_USER_PROD_API_KEY
-    as well as one of that customer's referral's production API keys via REFERRAL_CUSTOMER_PROD_API_KEY.
-    """
-    added_credit_card = partner_user_prod_client.referral_customer.add_credit_card(
-        referral_api_key=REFERRAL_CUSTOMER_PROD_API_KEY,
-        number=credit_card_details["number"],
-        expiration_month=credit_card_details["expiration_month"],
-        expiration_year=credit_card_details["expiration_year"],
-        cvc=credit_card_details["cvc"],
-    )
-
-    assert str.startswith(added_credit_card.id, "pm_")
-    assert added_credit_card.last4 == "6170"
-
-
-@patch("easypost.services.referral_customer_service.ReferralCustomerService._retrieve_easypost_stripe_api_key")
-@patch(
-    "easypost.services.referral_customer_service.ReferralCustomerService._create_stripe_token",
-    side_effect=Exception(),
-)
-def test_referral_add_credit_card_error(
-    mock_stripe_token,
-    mock_easypost_key,
-    credit_card_details,
-    partner_user_prod_client,
-):
-    """This test requires a partner customer's production API key via PARTNER_USER_PROD_API_KEY
-    as well as one of that customer's referral's production API keys via REFERRAL_CUSTOMER_PROD_API_KEY.
-    """
-    with pytest.raises(Exception) as error:
-        _ = partner_user_prod_client.referral_customer.add_credit_card(
-            referral_api_key=REFERRAL_CUSTOMER_PROD_API_KEY,
-            number=credit_card_details["number"],
-            expiration_month=credit_card_details["expiration_month"],
-            expiration_year=credit_card_details["expiration_year"],
-            cvc=credit_card_details["cvc"],
-        )
-
-    assert str(error.value) == "Could not send card details to Stripe, please try again later."
-
-
 @pytest.mark.vcr()
 def test_referral_customer_add_credit_card_from_stripe(partner_user_prod_client, credit_card_details, billing):
     """This test requires a referral customer's production API key via REFERRAL_CUSTOMER_PROD_API_KEY.
@@ -159,3 +106,12 @@ def test_referral_customer_add_bank_account_from_stripe(partner_user_prod_client
     assert (
         str(error.value) == "account_holder_name must be present when creating a Financial Connections payment method"
     )
+
+
+@pytest.mark.vcr()
+def test_referral_customer_retrieve_easypost_stripe_api_key(partner_user_prod_client):
+    """This test requires a partner customer's production API key via PARTNER_USER_PROD_API_KEY."""
+    public_key = partner_user_prod_client.referral_customer.retrieve_easypost_stripe_api_key()
+
+    assert isinstance(public_key, str)
+    assert public_key.startswith("pk_")