diff --git a/hls_vi/generate_metadata.py b/hls_vi/generate_metadata.py
index d75cf11..e5f9048 100644
--- a/hls_vi/generate_metadata.py
+++ b/hls_vi/generate_metadata.py
@@ -131,6 +131,11 @@ def generate_metadata(input_dir: Path, output_dir: Path) -> None:
 
     tree.find("DataFormat").text = "COG"
 
+    append_fmask_online_access_urls(
+        tree.find("OnlineAccessURLs"),
+        input_granule_ur,
+    )
+
     # ensure any added attributes are indented
     ET.indent(tree)
 
@@ -202,6 +207,38 @@ def set_additional_attribute(attrs: ElementBase, name: str, value: str) -> None:
         attrs.append(attr)
 
 
+def append_fmask_online_access_urls(access_urls: ElementBase, hls_granule_ur: str) -> None:
+    """Include links to Fmask layer from HLS granule in metadata
+
+    This is intended to help users find the relevant Fmask band without
+    having to duplicate it into the HLS-VI product. See,
+    https://github.com/NASA-IMPACT/hls-vi/issues/47
+    """
+    prefix = (
+        "HLSL30.020" if hls_granule_ur.startswith("HLS.L30")
+        else "HLSS30.020"
+    )
+
+    http_attr = Element("OnlineAccessURL", None, None)
+    http_attr_url = Element("URL", None, None)
+    http_attr_url.text = f"https://data.lpdaac.earthdatacloud.nasa.gov/lp-prod-protected/{prefix}/{hls_granule_ur}/{hls_granule_ur}.Fmask.tif"
+    http_attr_desc = Element("URLDescription", None, None)
+    http_attr_desc.text = f"Download Fmask quality layer {hls_granule_ur}.Fmask.tif"
+    http_attr.append(http_attr_url)
+    http_attr.append(http_attr_desc)
+
+    s3_attr = Element("OnlineAccessURL", None, None)
+    s3_attr_url = Element("URL", None, None)
+    s3_attr_url.text = f"s3://lp-prod-protected//{prefix}/{hls_granule_ur}/{hls_granule_ur}.Fmask.tif"
+    s3_attr_desc = Element("URLDescription", None, None)
+    s3_attr_desc.text = f"This link provides direct download access via S3 to the Fmask quality layer {hls_granule_ur}.Fmask.tif"
+    s3_attr.append(s3_attr_url)
+    s3_attr.append(s3_attr_desc)
+
+    access_urls.append(http_attr)
+    access_urls.append(s3_attr)
+
+
 def parse_args() -> Tuple[Path, Path]:
     short_options = "i:o:"
     long_options = ["instrument=", "inputdir=", "outputdir="]
diff --git a/tests/fixtures/HLS-VI.L30.T06WVS.2024120T211159.v2.0.cmr.xml b/tests/fixtures/HLS-VI.L30.T06WVS.2024120T211159.v2.0.cmr.xml
index c4a2b7e..c6911b5 100644
--- a/tests/fixtures/HLS-VI.L30.T06WVS.2024120T211159.v2.0.cmr.xml
+++ b/tests/fixtures/HLS-VI.L30.T06WVS.2024120T211159.v2.0.cmr.xml
@@ -248,6 +248,14 @@
     </AdditionalAttribute>
   </AdditionalAttributes>
   <OnlineAccessURLs>
+    <OnlineAccessURL>
+      <URL>https://data.lpdaac.earthdatacloud.nasa.gov/lp-prod-protected/HLSL30.020/HLS.L30.T06WVS.2024120T211159.v2.0/HLS.L30.T06WVS.2024120T211159.v2.0.Fmask.tif</URL>
+      <URLDescription>Download Fmask quality layer HLS.L30.T06WVS.2024120T211159.v2.0.Fmask.tif</URLDescription>
+    </OnlineAccessURL>
+    <OnlineAccessURL>
+      <URL>s3://lp-prod-protected//HLSL30.020/HLS.L30.T06WVS.2024120T211159.v2.0/HLS.L30.T06WVS.2024120T211159.v2.0.Fmask.tif</URL>
+      <URLDescription>This link provides direct download access via S3 to the Fmask quality layer HLS.L30.T06WVS.2024120T211159.v2.0.Fmask.tif</URLDescription>
+    </OnlineAccessURL>
   </OnlineAccessURLs>
   <OnlineResources>
   </OnlineResources>
diff --git a/tests/fixtures/HLS-VI.S30.T13RCN.2024128T173909.v2.0.cmr.xml b/tests/fixtures/HLS-VI.S30.T13RCN.2024128T173909.v2.0.cmr.xml
index 80e3062..00abbd0 100644
--- a/tests/fixtures/HLS-VI.S30.T13RCN.2024128T173909.v2.0.cmr.xml
+++ b/tests/fixtures/HLS-VI.S30.T13RCN.2024128T173909.v2.0.cmr.xml
@@ -310,6 +310,14 @@
     </AdditionalAttribute>
   </AdditionalAttributes>
   <OnlineAccessURLs>
+    <OnlineAccessURL>
+      <URL>https://data.lpdaac.earthdatacloud.nasa.gov/lp-prod-protected/HLSS30.020/HLS.S30.T13RCN.2024128T173909.v2.0/HLS.S30.T13RCN.2024128T173909.v2.0.Fmask.tif</URL>
+      <URLDescription>Download Fmask quality layer HLS.S30.T13RCN.2024128T173909.v2.0.Fmask.tif</URLDescription>
+    </OnlineAccessURL>
+    <OnlineAccessURL>
+      <URL>s3://lp-prod-protected//HLSS30.020/HLS.S30.T13RCN.2024128T173909.v2.0/HLS.S30.T13RCN.2024128T173909.v2.0.Fmask.tif</URL>
+      <URLDescription>This link provides direct download access via S3 to the Fmask quality layer HLS.S30.T13RCN.2024128T173909.v2.0.Fmask.tif</URLDescription>
+    </OnlineAccessURL>
   </OnlineAccessURLs>
   <OnlineResources>
   </OnlineResources>