diff --git a/obp-api/src/main/scala/deletion/DeleteAccountCascade.scala b/obp-api/src/main/scala/deletion/DeleteAccountCascade.scala
index f3756634ea..6588c515b0 100644
--- a/obp-api/src/main/scala/deletion/DeleteAccountCascade.scala
+++ b/obp-api/src/main/scala/deletion/DeleteAccountCascade.scala
@@ -33,7 +33,10 @@ import code.api.util.APIUtil.fullBoxOrException
 import code.api.util.ErrorMessages.CouldNotDeleteCascade
 import code.bankconnectors.Connector
 import code.cards.MappedPhysicalCard
+import code.counterpartyattribute.CounterpartyAttribute
+import code.counterpartylimit.CounterpartyLimit
 import code.entitlement.MappedEntitlement
+import code.metadata.counterparties.{MappedCounterparty, MappedCounterpartyBespoke, MappedCounterpartyMetadata, MappedCounterpartyWhereTag}
 import code.model.dataAccess.{BankAccountRouting, MappedBankAccount, MappedBankAccountData}
 import code.views.system.{AccountAccess, ViewDefinition}
 import code.webhook.MappedAccountWebhook
@@ -57,8 +60,10 @@ object DeleteAccountCascade {
         deleteAccountAttributes(bankId, accountId) ::
         deleteAccountWebhooks(bankId, accountId) ::
         deleteBankAccountData(bankId, accountId) ::
-        deleteCards(accountId) ::
+        deleteCards(bankId, accountId) ::
         deleteAccountRoutings(bankId, accountId) ::
+        deleteCounterparties(bankId, accountId) ::
+        deleteCounterpartyMetadata(bankId, accountId) ::
         deleteAccount(bankId, accountId) ::
         Nil
     doneTasks.forall(_ == true)
@@ -81,15 +86,19 @@ object DeleteAccountCascade {
     )
   }
   private def deleteEntitlements(bankId: BankId, accountId: AccountId): Boolean = {
-    val userIds = AccountAccess.findAll(By(AccountAccess.account_id, accountId.value)).map(_.user_fk.foreign.map(_.userId).getOrElse(""))
+    val userIds = AccountAccess.findAll(
+      By(AccountAccess.bank_id, bankId.value),
+      By(AccountAccess.account_id, accountId.value)
+    ).map(_.user_fk.foreign.map(_.userId).getOrElse(""))
     MappedEntitlement.bulkDelete_!!(
       By(MappedEntitlement.mBankId, bankId.value),
       ByList(MappedEntitlement.mUserId, userIds)
     )
   }
   
-  private def deleteCards(accountId: AccountId): Boolean = {
+  private def deleteCards(bankId: BankId, accountId: AccountId): Boolean = {
     MappedBankAccount.findAll(
+      By(MappedBankAccount.bank, bankId.value),
       By(MappedBankAccount.theAccountId, accountId.value)
     ) map (
       account =>
@@ -136,6 +145,46 @@ object DeleteAccountCascade {
     )
   }
 
+  // The counterparties this account created, with the rows that hang off each of them.
+  // Counterparties of other accounts that point at this account are theirs and are kept.
+  private def deleteCounterparties(bankId: BankId, accountId: AccountId): Boolean = {
+    val counterparties = MappedCounterparty.findAll(
+      By(MappedCounterparty.mThisBankId, bankId.value),
+      By(MappedCounterparty.mThisAccountId, accountId.value)
+    )
+    val primaryKeys = counterparties.map(_.id.get)
+    val counterpartyIds = counterparties.map(_.counterpartyId)
+    val bespokesDeleted = primaryKeys.isEmpty ||
+      MappedCounterpartyBespoke.bulkDelete_!!(ByList(MappedCounterpartyBespoke.mCounterparty, primaryKeys))
+    val attributesDeleted = counterpartyIds.isEmpty ||
+      CounterpartyAttribute.bulkDelete_!!(ByList(CounterpartyAttribute.CounterpartyId_, counterpartyIds))
+    val limitsDeleted = CounterpartyLimit.bulkDelete_!!(
+      By(CounterpartyLimit.BankId, bankId.value),
+      By(CounterpartyLimit.AccountId, accountId.value)
+    )
+    val counterpartiesDeleted = MappedCounterparty.bulkDelete_!!(
+      By(MappedCounterparty.mThisBankId, bankId.value),
+      By(MappedCounterparty.mThisAccountId, accountId.value)
+    )
+    bespokesDeleted && attributesDeleted && limitsDeleted && counterpartiesDeleted
+  }
+
+  // Metadata covers both the counterparties created on this account and the ones derived from its transactions.
+  private def deleteCounterpartyMetadata(bankId: BankId, accountId: AccountId): Boolean = {
+    val metadata = MappedCounterpartyMetadata.findAll(
+      By(MappedCounterpartyMetadata.thisBankId, bankId.value),
+      By(MappedCounterpartyMetadata.thisAccountId, accountId.value)
+    )
+    val locationIds = metadata.flatMap(m => List(m.physicalLocation.get, m.corporateLocation.get)).filter(_ > 0)
+    val locationsDeleted = locationIds.isEmpty ||
+      MappedCounterpartyWhereTag.bulkDelete_!!(ByList(MappedCounterpartyWhereTag.id, locationIds))
+    val metadataDeleted = MappedCounterpartyMetadata.bulkDelete_!!(
+      By(MappedCounterpartyMetadata.thisBankId, bankId.value),
+      By(MappedCounterpartyMetadata.thisAccountId, accountId.value)
+    )
+    locationsDeleted && metadataDeleted
+  }
+
   private def deleteTransactions(bankId: BankId, accountId: AccountId): Boolean = {
     val deletedTransactions: Box[List[Boolean]] =
       for(
diff --git a/obp-api/src/test/scala/code/api/v4_0_0/DeleteAccountCascadeTest.scala b/obp-api/src/test/scala/code/api/v4_0_0/DeleteAccountCascadeTest.scala
index 2bd939c43a..fead73009d 100644
--- a/obp-api/src/test/scala/code/api/v4_0_0/DeleteAccountCascadeTest.scala
+++ b/obp-api/src/test/scala/code/api/v4_0_0/DeleteAccountCascadeTest.scala
@@ -37,10 +37,14 @@ import code.api.util.ApiRole.CanDeleteAccountCascade
 import code.api.util.ErrorMessages.{UserHasMissingRoles, AuthenticatedUserIsRequired}
 import code.api.v3_1_0.CreateAccountResponseJsonV310
 import code.api.v4_0_0.Http4s400.Implementations4_0_0
-import code.entitlement.Entitlement
+import code.cards.MappedPhysicalCard
+import code.entitlement.{Entitlement, MappedEntitlement}
+import code.model.dataAccess.MappedBankAccount
 import com.github.dwickern.macros.NameOf.nameOf
-import com.openbankproject.commons.model.{AmountOfMoneyJsonV121, ErrorMessage}
+import com.openbankproject.commons.model.{AccountId, AmountOfMoneyJsonV121, BankId, ErrorMessage}
 import com.openbankproject.commons.util.ApiVersion
+import net.liftweb.mapper.By
+import net.liftweb.util.Helpers.randomString
 import org.json4s.native.Serialization.write
 import org.scalatest.Tag
 
@@ -139,6 +143,81 @@ class DeleteAccountCascadeTest extends V400ServerSetup {
       makeDeleteRequest(request400).code should equal(404)
     }
   }
-  
+
+  feature(s"test $ApiEndpoint1 version $VersionOfApi - cards") {
+    scenario("Deleting an account keeps the cards of an account with the same ACCOUNT_ID at another bank", ApiEndpoint1, VersionOfApi) {
+      Given("Two banks that each have an account with the same ACCOUNT_ID, each with a card")
+      val bankId = BankId(randomString(10))
+      val otherBankId = BankId(randomString(10))
+      createBank(bankId.value)
+      createBank(otherBankId.value)
+      val accountId = AccountId(randomString(10))
+      createAccountRelevantResource(Some(resourceUser1), bankId, accountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser1), otherBankId, accountId, "EUR")
+
+      def addCard(bank: BankId): String = {
+        val account = MappedBankAccount.find(
+          By(MappedBankAccount.bank, bank.value),
+          By(MappedBankAccount.theAccountId, accountId.value)
+        ).openOrThrowException("test account not found")
+        MappedPhysicalCard.create
+          .mBankId(bank.value)
+          .mAccount(account.id.get)
+          .mBankCardNumber(randomString(16))
+          .mSerialNumber(randomString(10))
+          .saveMe()
+          .mCardId.get
+      }
+      def cardExists(cardId: String): Boolean = MappedPhysicalCard.find(By(MappedPhysicalCard.mCardId, cardId)).isDefined
+      val card = addCard(bankId)
+      val otherBankCard = addCard(otherBankId)
+
+      When("We delete the account at the first bank with the cascading endpoint")
+      Entitlement.entitlement.vend.addEntitlement(bankId.value, resourceUser1.userId, ApiRole.canDeleteAccountCascade.toString)
+      val request = (v4_0_0_Request / "management" / "cascading" / "banks" / bankId.value /
+        "accounts" / accountId.value).DELETE <@ (user1)
+      val response = makeDeleteRequest(request)
+
+      Then("We should get a 200")
+      response.code should equal(200)
+
+      And("The deleted account's card is gone and the other bank's card is kept")
+      cardExists(card) should equal(false)
+      cardExists(otherBankCard) should equal(true)
+    }
+  }
+
+  feature(s"test $ApiEndpoint1 version $VersionOfApi - entitlements") {
+    scenario("Deleting an account keeps the entitlements of users who only use an account with the same ACCOUNT_ID at another bank", ApiEndpoint1, VersionOfApi) {
+      Given("Two banks that each have an account with the same ACCOUNT_ID, owned by different users")
+      val bankId = BankId(randomString(10))
+      val otherBankId = BankId(randomString(10))
+      createBank(bankId.value)
+      createBank(otherBankId.value)
+      val accountId = AccountId(randomString(10))
+      createAccountRelevantResource(Some(resourceUser1), bankId, accountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser2), otherBankId, accountId, "EUR")
+
+      And("The other bank's account owner has an entitlement at the first bank")
+      Entitlement.entitlement.vend.addEntitlement(bankId.value, resourceUser2.userId, ApiRole.canCreateAccount.toString)
+      def otherOwnerEntitlements: Long = MappedEntitlement.count(
+        By(MappedEntitlement.mBankId, bankId.value),
+        By(MappedEntitlement.mUserId, resourceUser2.userId)
+      )
+      otherOwnerEntitlements should equal(1L)
+
+      When("We delete the account at the first bank with the cascading endpoint")
+      Entitlement.entitlement.vend.addEntitlement(bankId.value, resourceUser1.userId, ApiRole.canDeleteAccountCascade.toString)
+      val request = (v4_0_0_Request / "management" / "cascading" / "banks" / bankId.value /
+        "accounts" / accountId.value).DELETE <@ (user1)
+      val response = makeDeleteRequest(request)
+
+      Then("We should get a 200")
+      response.code should equal(200)
+
+      And("The other bank's account owner keeps the entitlement")
+      otherOwnerEntitlements should equal(1L)
+    }
+  }
 
 }
diff --git a/obp-api/src/test/scala/code/api/v4_0_0/DeleteCascadeCounterpartiesTest.scala b/obp-api/src/test/scala/code/api/v4_0_0/DeleteCascadeCounterpartiesTest.scala
new file mode 100644
index 0000000000..f2cee8514f
--- /dev/null
+++ b/obp-api/src/test/scala/code/api/v4_0_0/DeleteCascadeCounterpartiesTest.scala
@@ -0,0 +1,201 @@
+/**
+Open Bank Project - API
+Copyright (C) 2011-2026, TESOBE GmbH.
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Email: contact@tesobe.com
+TESOBE GmbH.
+Osloer Strasse 16/17
+Berlin 13359, Germany
+
+This product includes software developed at
+TESOBE (http://www.tesobe.com/)
+
+  */
+
+package code.api.v4_0_0
+
+import code.api.Constant
+import code.api.util.APIUtil.OAuth._
+import code.api.util.ApiRole
+import code.api.util.ErrorMessages.attemptedToOpenAnEmptyBox
+import code.api.v4_0_0.Http4s400.Implementations4_0_0
+import code.counterpartyattribute.{CounterpartyAttribute, CounterpartyAttributeX}
+import code.counterpartylimit.{CounterpartyLimit, CounterpartyLimitProvider}
+import code.entitlement.Entitlement
+import code.metadata.counterparties.{Counterparties, MappedCounterparty, MappedCounterpartyBespoke, MappedCounterpartyMetadata, MappedCounterpartyWhereTag}
+import com.github.dwickern.macros.NameOf.nameOf
+import com.openbankproject.commons.model.enums.CounterpartyAttributeType
+import com.openbankproject.commons.model.{AccountId, BankId, CounterpartyBespoke, CounterpartyId, CounterpartyTrait}
+import com.openbankproject.commons.util.ApiVersion
+import net.liftweb.mapper.{By, ByList}
+import net.liftweb.util.Helpers.randomString
+import org.scalatest.Tag
+
+import java.util.Date
+import scala.concurrent.Await
+import scala.concurrent.duration._
+
+class DeleteCascadeCounterpartiesTest extends V400ServerSetup {
+
+  object VersionOfApi extends Tag(ApiVersion.v4_0_0.toString)
+  object ApiEndpoint1 extends Tag(nameOf(Implementations4_0_0.deleteAccountCascade))
+  object ApiEndpoint2 extends Tag(nameOf(Implementations4_0_0.deleteBankCascade))
+
+  private val ownerView = Constant.SYSTEM_OWNER_VIEW_ID
+
+  private case class Seeded(bankId: BankId, accountId: AccountId, counterparty: CounterpartyTrait, locationIds: List[Long])
+
+  /** A counterparty on the given account, with rows in every table that hangs off it. */
+  private def createCounterpartyWithChildren(bankId: BankId, accountId: AccountId): Seeded = {
+    val counterparty = Counterparties.counterparties.vend.createCounterparty(
+      createdByUserId = resourceUser1.userId,
+      thisBankId = bankId.value,
+      thisAccountId = accountId.value,
+      thisViewId = ownerView,
+      name = randomString(20),
+      otherAccountRoutingScheme = "IBAN",
+      otherAccountRoutingAddress = "DE89370400440532013000",
+      otherBankRoutingScheme = "BIC",
+      otherBankRoutingAddress = "COBADEFFXXX",
+      otherBranchRoutingScheme = "OBP",
+      otherBranchRoutingAddress = "Berlin",
+      isBeneficiary = true,
+      otherAccountSecondaryRoutingScheme = "IBAN",
+      otherAccountSecondaryRoutingAddress = "DE89370400440532013000",
+      description = "cascade test payee",
+      currency = "EUR",
+      bespoke = List(CounterpartyBespoke("key", "value"))
+    ).openOrThrowException(attemptedToOpenAnEmptyBox)
+
+    val metadata = Counterparties.counterparties.vend
+      .getOrCreateMetadata(bankId, accountId, counterparty.counterpartyId, counterparty.name)
+      .openOrThrowException(attemptedToOpenAnEmptyBox)
+    metadata.addPhysicalLocation(resourceUser1.userPrimaryKey, new Date(), 13.4, 52.5) should be(true)
+    metadata.addCorporateLocation(resourceUser1.userPrimaryKey, new Date(), 11.6, 48.1) should be(true)
+    Await.result(
+      CounterpartyAttributeX.counterpartyAttributeProvider.vend.createOrUpdateCounterpartyAttribute(
+        CounterpartyId(counterparty.counterpartyId), None, "TAX_NUMBER", CounterpartyAttributeType.STRING, "123", Some(true)),
+      10.seconds
+    ).openOrThrowException(attemptedToOpenAnEmptyBox)
+    Await.result(
+      CounterpartyLimitProvider.counterpartyLimit.vend.createOrUpdateCounterpartyLimit(
+        bankId.value, accountId.value, ownerView, counterparty.counterpartyId,
+        "EUR", BigDecimal(100), BigDecimal(1000), 10, BigDecimal(10000), 100, BigDecimal(100000), 1000),
+      10.seconds
+    ).openOrThrowException(attemptedToOpenAnEmptyBox)
+
+    val storedMetadata = MappedCounterpartyMetadata.find(By(MappedCounterpartyMetadata.counterpartyId, counterparty.counterpartyId))
+      .openOrThrowException(attemptedToOpenAnEmptyBox)
+    Seeded(bankId, accountId, counterparty, List(storedMetadata.physicalLocation.get, storedMetadata.corporateLocation.get))
+  }
+
+  /** Rows left in each counterparty table for one seeded counterparty. */
+  private def remainingRows(seeded: Seeded): Map[String, Long] = {
+    val Seeded(bankId, accountId, counterparty, locationIds) = seeded
+    val counterpartyId = counterparty.counterpartyId
+    val primaryKey = counterparty.asInstanceOf[MappedCounterparty].id.get
+    Map(
+      "counterparty" -> MappedCounterparty.count(By(MappedCounterparty.mCounterPartyId, counterpartyId)),
+      "bespoke" -> MappedCounterpartyBespoke.count(By(MappedCounterpartyBespoke.mCounterparty, primaryKey)),
+      "metadata" -> MappedCounterpartyMetadata.count(
+        By(MappedCounterpartyMetadata.thisBankId, bankId.value),
+        By(MappedCounterpartyMetadata.thisAccountId, accountId.value),
+        By(MappedCounterpartyMetadata.counterpartyId, counterpartyId)),
+      "attribute" -> CounterpartyAttribute.count(By(CounterpartyAttribute.CounterpartyId_, counterpartyId)),
+      "limit" -> CounterpartyLimit.count(By(CounterpartyLimit.CounterpartyId, counterpartyId)),
+      "location" -> MappedCounterpartyWhereTag.count(ByList(MappedCounterpartyWhereTag.id, locationIds))
+    )
+  }
+
+  private val nothingLeft =
+    Map("counterparty" -> 0L, "bespoke" -> 0L, "metadata" -> 0L, "attribute" -> 0L, "limit" -> 0L, "location" -> 0L)
+  private val untouched =
+    Map("counterparty" -> 1L, "bespoke" -> 1L, "metadata" -> 1L, "attribute" -> 1L, "limit" -> 1L, "location" -> 2L)
+
+  feature(s"test $ApiEndpoint1 version $VersionOfApi - counterparties") {
+    scenario("Deleting an account deletes its own counterparties and leaves other accounts' counterparties alone", ApiEndpoint1, VersionOfApi) {
+      Given("Two banks that each have an account with the same ACCOUNT_ID, plus a second account in the first bank")
+      val bankId = BankId(randomString(10))
+      val otherBankId = BankId(randomString(10))
+      createBank(bankId.value)
+      createBank(otherBankId.value)
+      val accountId = AccountId(randomString(10))
+      val siblingAccountId = AccountId(randomString(10))
+      createAccountRelevantResource(Some(resourceUser1), bankId, accountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser1), otherBankId, accountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser1), bankId, siblingAccountId, "EUR")
+
+      And("A counterparty with bespoke fields, metadata with two locations, an attribute and a limit on each account")
+      val target = createCounterpartyWithChildren(bankId, accountId)
+      val sameIdOtherBank = createCounterpartyWithChildren(otherBankId, accountId)
+      val sibling = createCounterpartyWithChildren(bankId, siblingAccountId)
+      remainingRows(target) should equal(untouched)
+
+      When("We delete the first account with the cascading endpoint")
+      Entitlement.entitlement.vend.addEntitlement(bankId.value, resourceUser1.userId, ApiRole.canDeleteAccountCascade.toString)
+      val request = (v4_0_0_Request / "management" / "cascading" / "banks" / bankId.value /
+        "accounts" / accountId.value).DELETE <@ (user1)
+      val response = makeDeleteRequest(request)
+
+      Then("We should get a 200")
+      response.code should equal(200)
+
+      And("The account's counterparty and every row that hangs off it are gone")
+      remainingRows(target) should equal(nothingLeft)
+
+      And("The counterparty of the same ACCOUNT_ID at another bank is untouched")
+      remainingRows(sameIdOtherBank) should equal(untouched)
+
+      And("The counterparty of the other account at the same bank is untouched")
+      remainingRows(sibling) should equal(untouched)
+    }
+  }
+
+  feature(s"test $ApiEndpoint2 version $VersionOfApi - counterparties") {
+    scenario("Deleting a bank deletes the counterparties of all its accounts and leaves other banks alone", ApiEndpoint2, VersionOfApi) {
+      Given("A bank with two accounts, and another bank with an account that has the same ACCOUNT_ID")
+      val bankId = BankId(randomString(10))
+      val otherBankId = BankId(randomString(10))
+      createBank(bankId.value)
+      createBank(otherBankId.value)
+      val accountId = AccountId(randomString(10))
+      val secondAccountId = AccountId(randomString(10))
+      createAccountRelevantResource(Some(resourceUser1), bankId, accountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser1), bankId, secondAccountId, "EUR")
+      createAccountRelevantResource(Some(resourceUser1), otherBankId, accountId, "EUR")
+
+      val first = createCounterpartyWithChildren(bankId, accountId)
+      val second = createCounterpartyWithChildren(bankId, secondAccountId)
+      val otherBank = createCounterpartyWithChildren(otherBankId, accountId)
+
+      When("We delete the bank with the cascading endpoint")
+      Entitlement.entitlement.vend.addEntitlement(bankId.value, resourceUser1.userId, ApiRole.canDeleteBankCascade.toString)
+      val request = (v4_0_0_Request / "management" / "cascading" / "banks" / bankId.value).DELETE <@ (user1)
+      val response = makeDeleteRequest(request)
+
+      Then("We should get a 200")
+      response.code should equal(200)
+
+      And("The counterparties of both accounts and their child rows are gone")
+      remainingRows(first) should equal(nothingLeft)
+      remainingRows(second) should equal(nothingLeft)
+
+      And("The counterparty at the other bank is untouched")
+      remainingRows(otherBank) should equal(untouched)
+    }
+  }
+
+}