diff --git a/app/lists/mirror_mapping.py b/app/lists/mirror_mapping.py
index 659326d..8414611 100644
--- a/app/lists/mirror_mapping.py
+++ b/app/lists/mirror_mapping.py
@@ -1,10 +1,12 @@
 #  pylint: disable=too-few-public-methods
 
 import builtins
+import datetime
 from typing import Dict, List, Union
 
 from flask import current_app
 from pydantic import BaseModel, Field
+from pydantic.typing import Optional
 from tldextract import extract
 
 from app.models.base import Group, Pool
@@ -15,6 +17,8 @@ class MMMirror(BaseModel):
     origin_domain: str = Field(description="The full origin domain name")
     origin_domain_normalized: str = Field(description="The origin_domain with \"www.\" removed, if present")
     origin_domain_root: str = Field(description="The registered domain name of the origin, excluding subdomains")
+    valid_from: str = Field(description="The date on which the mirror was added to the system")
+    valid_to: Optional[str] = Field(description="The date on which the mirror was decommissioned")
 
 
 class MirrorMapping(BaseModel):
@@ -39,7 +43,9 @@ def mirror_mapping(pool: Pool) -> Dict[str, Union[str, Dict[str, str]]]:
             d.url.lstrip("https://"): MMMirror(
                 origin_domain=d.origin.domain_name,
                 origin_domain_normalized=d.origin.domain_name.replace("www.", ""),
-                origin_domain_root=extract(d.origin.domain_name).registered_domain
+                origin_domain_root=extract(d.origin.domain_name).registered_domain,
+                valid_from=d.origin.added.isoformat(),
+                valid_to=d.origin.destroyed.isoformat() if d.origin.destroyed is not None else None
             ) for d in Proxy.query.all() if d.url is not None
         },
         s3_buckets=[