diff --git a/api/paidAction/itemCreate.js b/api/paidAction/itemCreate.js
index d6fb603f7..f36ea60b6 100644
--- a/api/paidAction/itemCreate.js
+++ b/api/paidAction/itemCreate.js
@@ -42,7 +42,7 @@ export async function getCost ({ subName, parentId, uploadIds, boost = 0, bio },
   const [{ cost }] = await models.$queryRaw`
     SELECT ${baseCost}::INTEGER
       * POWER(10, item_spam(${parseInt(parentId)}::INTEGER, ${me?.id ?? USER_ID.anon}::INTEGER,
-          ${me?.id && !bio ? ITEM_SPAM_INTERVAL : ANON_ITEM_SPAM_INTERVAL}::INTERVAL))
+          ${me?.id && !bio ? ITEM_SPAM_INTERVAL : ANON_ITEM_SPAM_INTERVAL}::INTERVAL, ${subName}::TEXT))
       * ${me ? 1 : 100}::INTEGER
       + (SELECT "nUnpaid" * "uploadFeesMsats"
           FROM upload_fees(${me?.id || USER_ID.anon}::INTEGER, ${uploadIds}::INTEGER[]))
diff --git a/api/resolvers/item.js b/api/resolvers/item.js
index b1a53e544..f4527104f 100644
--- a/api/resolvers/item.js
+++ b/api/resolvers/item.js
@@ -350,11 +350,11 @@ function typeClause (type) {
 
 export default {
   Query: {
-    itemRepetition: async (parent, { parentId }, { me, models }) => {
+    itemRepetition: async (parent, { parentId, sub }, { me, models }) => {
       if (!me) return 0
       // how many of the parents starting at parentId belong to me
-      const [{ item_spam: count }] = await models.$queryRawUnsafe(`SELECT item_spam($1::INTEGER, $2::INTEGER, '${ITEM_SPAM_INTERVAL}')`,
-        Number(parentId), Number(me.id))
+      const [{ item_spam: count }] = await models.$queryRawUnsafe(`SELECT item_spam($1::INTEGER, $2::INTEGER, '${ITEM_SPAM_INTERVAL}', $3::TEXT)`,
+        Number(parentId), Number(me.id), sub)
 
       return count
     },
diff --git a/api/typeDefs/item.js b/api/typeDefs/item.js
index 730f61830..34a6dbb0e 100644
--- a/api/typeDefs/item.js
+++ b/api/typeDefs/item.js
@@ -10,7 +10,7 @@ export default gql`
     search(q: String, sub: String, cursor: String, what: String, sort: String, when: String, from: String, to: String): Items
     auctionPosition(sub: String, id: ID, boost: Int): Int!
     boostPosition(sub: String, id: ID, boost: Int): BoostPositions!
-    itemRepetition(parentId: ID): Int!
+    itemRepetition(parentId: ID, sub: String): Int!
   }
 
   type BoostPositions {
diff --git a/components/fee-button.js b/components/fee-button.js
index d490c4499..98b56c7b9 100644
--- a/components/fee-button.js
+++ b/components/fee-button.js
@@ -37,10 +37,15 @@ export function postCommentBaseLineItems ({ baseCost = 1, comment = false, me })
   }
 }
 
-export function postCommentUseRemoteLineItems ({ parentId } = {}) {
-  const query = parentId
-    ? gql`{ itemRepetition(parentId: "${parentId}") }`
-    : gql`{ itemRepetition }`
+export function postCommentUseRemoteLineItems ({ sub, parentId } = {}) {
+  const query = parentId && sub
+    ? gql`{ itemRepetition(parentId: "${parentId}", sub: "${sub}") }`
+    : (parentId
+        ? gql`{ itemRepetition(parentId: "${parentId}") }`
+        : (sub
+            ? gql`{ itemRepetition(sub: "${sub}") }`
+            : gql`{ itemRepetition }`
+          ))
 
   return function useRemoteLineItems () {
     const [line, setLine] = useState({})
diff --git a/components/post.js b/components/post.js
index 6245d1a16..7be73d8fb 100644
--- a/components/post.js
+++ b/components/post.js
@@ -150,7 +150,7 @@ export function PostForm ({ type, sub, children }) {
   return (
     <FeeButtonProvider
       baseLineItems={sub ? postCommentBaseLineItems({ baseCost: sub.baseCost, me: !!me }) : undefined}
-      useRemoteLineItems={postCommentUseRemoteLineItems()}
+      useRemoteLineItems={postCommentUseRemoteLineItems({ sub: sub?.name })}
     >
       <FormType sub={sub}>{children}</FormType>
     </FeeButtonProvider>
diff --git a/components/reply.js b/components/reply.js
index ec12d0a5f..b45996a72 100644
--- a/components/reply.js
+++ b/components/reply.js
@@ -71,7 +71,7 @@ export default forwardRef(function Reply ({
         // no lag for itemRepetition
         if (!item.mine && me) {
           cache.updateQuery({
-            query: gql`{ itemRepetition(parentId: "${parentId}") }`
+            query: gql`{ itemRepetition(parentId: "${parentId}", sub: "${sub?.name}") }`
           }, data => {
             return {
               itemRepetition: (data?.itemRepetition || 0) + 1
@@ -162,7 +162,7 @@ export default forwardRef(function Reply ({
         <div className={styles.reply}>
           <FeeButtonProvider
             baseLineItems={postCommentBaseLineItems({ baseCost: sub?.replyCost ?? 1, comment: true, me: !!me })}
-            useRemoteLineItems={postCommentUseRemoteLineItems({ parentId: item.id, me: !!me })}
+            useRemoteLineItems={postCommentUseRemoteLineItems({ parentId: item.id, sub: sub?.name, me: !!me })}
           >
             <Form
               initial={{
diff --git a/prisma/migrations/20250314104901_pass_sub_to_item_spam/migration.sql b/prisma/migrations/20250314104901_pass_sub_to_item_spam/migration.sql
new file mode 100644
index 000000000..1d4930f5b
--- /dev/null
+++ b/prisma/migrations/20250314104901_pass_sub_to_item_spam/migration.sql
@@ -0,0 +1,51 @@
+-- exclude posts in own subs from spam detection
+CREATE OR REPLACE FUNCTION item_spam(parent_id INTEGER, user_id INTEGER, within INTERVAL, sub_name TEXT)
+RETURNS INTEGER
+LANGUAGE plpgsql
+AS $$
+DECLARE
+    repeats INTEGER;
+    self_replies INTEGER;
+BEGIN
+    -- no fee escalation
+    IF within = interval '0' THEN
+        RETURN 0;
+    END IF;
+
+    IF sub_name IS NOT NULL AND user_id = (SELECT "Sub"."userId" FROM "Sub" WHERE "Sub"."name" = sub_name) THEN
+        RETURN 0;
+    END IF;
+
+    SELECT count(*) INTO repeats
+    FROM "Item"
+    LEFT JOIN "Sub" ON "Sub"."name" = "Item"."subName"
+    WHERE (
+        (parent_id IS NULL AND "parentId" IS NULL)
+        OR
+        ("parentId" = parent_id AND user_id <> (SELECT i."userId" FROM "Item" i WHERE i.id = "Item"."rootId"))
+    )
+    AND "Item"."userId" = user_id
+    AND "bio" = 'f'
+    AND ("Sub"."name" IS NULL OR "Sub"."userId" <> user_id)
+    AND "Item".created_at > now_utc() - within;
+
+    IF parent_id IS NULL THEN
+        RETURN repeats;
+    END IF;
+
+    WITH RECURSIVE base AS (
+        SELECT "Item".id, "Item"."parentId", "Item"."userId"
+        FROM "Item"
+        WHERE id = parent_id
+        AND "userId" = user_id
+        AND created_at > now_utc() - within
+        AND user_id <> (SELECT i."userId" FROM "Item" i WHERE i.id = "Item"."rootId")
+      UNION ALL
+        SELECT "Item".id, "Item"."parentId", "Item"."userId"
+        FROM base p
+        JOIN "Item" ON "Item".id = p."parentId" AND "Item"."userId" = p."userId" AND "Item".created_at > now_utc() - within)
+    SELECT count(*) INTO self_replies FROM base;
+
+    RETURN repeats + self_replies;
+END;
+$$;