diff --git a/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/fakeData.ts b/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/fakeData.ts
index d0678b65624f..ea80a1aadcdf 100644
--- a/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/fakeData.ts
+++ b/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/fakeData.ts
@@ -1,3 +1,4 @@
+import { NO, YES } from '@island.is/application/core'
 import { ApplicationWithAttachments } from '@island.is/application/types'
 import { EstateInfo } from '@island.is/clients/syslumenn'
 
@@ -59,7 +60,7 @@ export const getFakeEstateInfo = (
         share: 100,
       },
     ],
-    knowledgeOfOtherWills: 'yes',
+    knowledgeOfOtherWills: YES,
     ships: [],
     flyers: [],
     guns: [
@@ -81,6 +82,7 @@ export const getFakeEstateInfo = (
         nationalId: '0101303019',
         email: 'fake@email.com',
         phone: '9999999',
+        foreignCitizenship: [NO],
       },
       {
         name: 'Gervimaður Færeyjar',
@@ -88,6 +90,7 @@ export const getFakeEstateInfo = (
         nationalId: '0101302399',
         email: 'fake2@email.com',
         phone: '9999998',
+        foreignCitizenship: [NO],
       },
       {
         name: 'Gervimaður Bretland',
@@ -95,6 +98,7 @@ export const getFakeEstateInfo = (
         nationalId: '0101304929',
         email: 'fake3@email.com',
         phone: '9999997',
+        foreignCitizenship: [NO],
       },
     ],
     caseNumber: `2020-00012${nationalIdOfDeceased.slice(-4)}`,
diff --git a/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/mappers.ts b/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/mappers.ts
index 6f8b31b14f0e..e99558eaa08a 100644
--- a/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/mappers.ts
+++ b/libs/application/template-api-modules/src/lib/modules/templates/estate/utils/mappers.ts
@@ -8,7 +8,7 @@ import { estateSchema } from '@island.is/application/templates/estate'
 import { infer as zinfer } from 'zod'
 import { UploadData } from '../types'
 import { filterEmptyObjects } from './filters'
-import { info } from 'kennitala'
+import { info, isPerson } from 'kennitala'
 import { NO, YES } from '@island.is/application/core'
 
 type EstateSchema = zinfer<typeof estateSchema>
@@ -41,11 +41,7 @@ const estateMemberMapper = (element: EstateMember) => {
       : info(element?.nationalId).age < 18
       ? { nationalId: '', name: '', phone: '', email: '' }
       : undefined,
-    foreignCitizenship:
-      element.foreignCitizenship ??
-      (!element.nationalId || element.nationalId.endsWith('0000')
-        ? [YES]
-        : [NO]),
+    foreignCitizenship: isPerson(element.nationalId) ? [YES] : [NO],
   }
 }
 
diff --git a/libs/clients/syslumenn/src/lib/syslumennClient.utils.ts b/libs/clients/syslumenn/src/lib/syslumennClient.utils.ts
index 0a5258f72ced..0c8f9551316c 100644
--- a/libs/clients/syslumenn/src/lib/syslumennClient.utils.ts
+++ b/libs/clients/syslumenn/src/lib/syslumennClient.utils.ts
@@ -402,11 +402,6 @@ export const estateMemberMapper = (estateRaw: Erfingar): EstateMember => {
     advocate: estateRaw.malsvari ? mapAdvocate(estateRaw.malsvari) : undefined,
     email: estateRaw.netfang ?? '',
     phone: estateRaw.simi ?? '',
-    // We can assume that heir is a foreign citizen if national id is missing or ends with '0000'
-    foreignCitizenship:
-      !estateRaw.kennitala || estateRaw.kennitala.endsWith('0000')
-        ? ['yes']
-        : ['no'],
   }
 }