diff --git a/apps/wiki/content/docs/concepts/billing.mdx b/apps/wiki/content/docs/concepts/billing.mdx
index 359c94c..e5e80f2 100644
--- a/apps/wiki/content/docs/concepts/billing.mdx
+++ b/apps/wiki/content/docs/concepts/billing.mdx
@@ -15,4 +15,5 @@ After upgrading from the free tier, you will be charged per email sent at $0.001
 You are able to monitor your email usage and set billing limits per category in the billing tab of the project settings.
 
 ## Special considerations
-- Emails that contain an attachment will incur double the cost (e.g. 1 email with attachment = 2 emails for billing purposes)
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+- Emails that contain an attachment will incur double the cost (e.g. 1 email with attachment = 2 emails for billing purposes)
+- Inbound emails count towards the email limit at the same rate as outbound emails (e.g. 1 inbound email = 1 email for billing purposes)
\ No newline at end of file