diff --git a/swh/web/inbound_email/utils.py b/swh/web/inbound_email/utils.py
new file mode 100644
--- /dev/null
+++ b/swh/web/inbound_email/utils.py
@@ -0,0 +1,63 @@
+# Copyright (C) 2022  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU Affero General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+from dataclasses import dataclass
+from email.headerregistry import Address
+from email.message import EmailMessage
+from typing import List, Optional
+
+
+def extract_recipients(message: EmailMessage) -> List[Address]:
+    """Extract a list of recipients of the `message`.
+
+    This uses the ``To`` and ``Cc`` fields.
+    """
+
+    ret = []
+
+    for header_name in ("to", "cc"):
+        for header in message.get_all(header_name, []):
+            ret.extend(header.addresses)
+
+    return ret
+
+
+@dataclass
+class AddressMatch:
+    """Data related to a recipient match"""
+
+    recipient: Address
+    """The original recipient that matched the expected address"""
+    extension: Optional[str]
+    """The parsed +-extension of the matched recipient address"""
+
+
+def recipient_matches(message: EmailMessage, address: str) -> List[AddressMatch]:
+    """Check whether any of the message recipients match the given address.
+
+    The match is case-insensitive, which is not really RFC-compliant but matches what
+    most people would expect.
+
+    This function supports "+-addressing", where the local part of the email address is
+    appended with a `+`.
+
+    """
+
+    ret = []
+
+    parsed_address = Address(addr_spec=address.lower())
+
+    for recipient in extract_recipients(message):
+        if recipient.domain.lower() != parsed_address.domain:
+            continue
+
+        base_username, _, extension = recipient.username.partition("+")
+
+        if base_username.lower() != parsed_address.username:
+            continue
+
+        ret.append(AddressMatch(recipient=recipient, extension=extension or None))
+
+    return ret
diff --git a/swh/web/tests/inbound_email/test_utils.py b/swh/web/tests/inbound_email/test_utils.py
new file mode 100644
--- /dev/null
+++ b/swh/web/tests/inbound_email/test_utils.py
@@ -0,0 +1,113 @@
+# Copyright (C) 2022  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU Affero General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+from email.headerregistry import Address
+from email.message import EmailMessage
+
+from swh.web.inbound_email import utils
+
+
+def test_extract_recipients():
+    message = EmailMessage()
+    assert utils.extract_recipients(message) == []
+
+    message["To"] = "Test Recipient <test-recipient@example.com>"
+
+    assert utils.extract_recipients(message) == [
+        Address(display_name="Test Recipient", addr_spec="test-recipient@example.com")
+    ]
+
+    message["Cc"] = (
+        "test-recipient-2@example.com, "
+        "Another Test Recipient <test-recipient-3@example.com>"
+    )
+    assert utils.extract_recipients(message) == [
+        Address(display_name="Test Recipient", addr_spec="test-recipient@example.com"),
+        Address(addr_spec="test-recipient-2@example.com"),
+        Address(
+            display_name="Another Test Recipient",
+            addr_spec="test-recipient-3@example.com",
+        ),
+    ]
+
+    del message["To"]
+    assert utils.extract_recipients(message) == [
+        Address(addr_spec="test-recipient-2@example.com"),
+        Address(
+            display_name="Another Test Recipient",
+            addr_spec="test-recipient-3@example.com",
+        ),
+    ]
+
+
+def test_recipient_matches():
+    message = EmailMessage()
+    assert utils.recipient_matches(message, "match@example.com") == []
+
+    message = EmailMessage()
+    message["to"] = "nomatch@example.com"
+    assert utils.recipient_matches(message, "match@example.com") == []
+
+    message = EmailMessage()
+    message["to"] = "match@example.com"
+    assert utils.recipient_matches(message, "match@example.com") == [
+        utils.AddressMatch(
+            recipient=Address(addr_spec="match@example.com"), extension=None
+        )
+    ]
+
+    message = EmailMessage()
+    message["to"] = "match+extension@example.com"
+    assert utils.recipient_matches(message, "match@example.com") == [
+        utils.AddressMatch(
+            recipient=Address(addr_spec="match+extension@example.com"),
+            extension="extension",
+        )
+    ]
+
+    message = EmailMessage()
+    message["to"] = "match+weird+plussed+extension@example.com"
+    assert utils.recipient_matches(message, "match@example.com") == [
+        utils.AddressMatch(
+            recipient=Address(addr_spec="match+weird+plussed+extension@example.com"),
+            extension="weird+plussed+extension",
+        )
+    ]
+
+    message = EmailMessage()
+    message["to"] = "nomatch@example.com"
+    message["cc"] = ", ".join(
+        (
+            "match@example.com",
+            "match@notamatch.example.com",
+            "Another Match <match+extension@example.com>",
+        )
+    )
+    assert utils.recipient_matches(message, "match@example.com") == [
+        utils.AddressMatch(
+            recipient=Address(addr_spec="match@example.com"), extension=None,
+        ),
+        utils.AddressMatch(
+            recipient=Address(
+                display_name="Another Match", addr_spec="match+extension@example.com"
+            ),
+            extension="extension",
+        ),
+    ]
+
+
+def test_recipient_matches_casemapping():
+    message = EmailMessage()
+    message["to"] = "match@example.com"
+
+    assert utils.recipient_matches(message, "Match@Example.Com")
+    assert utils.recipient_matches(message, "match@example.com")
+
+    message = EmailMessage()
+    message["to"] = "Match+weirdCaseMapping@Example.Com"
+
+    matches = utils.recipient_matches(message, "match@example.com")
+    assert matches
+    assert matches[0].extension == "weirdCaseMapping"