diff --git a/docs/source/conf.py b/docs/source/conf.py
index a6c6ee3f..f03dbcd6 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -66,11 +66,11 @@
 
 extlinks = {
     "pandas_api_docs": (
-        "https://pandas.pydata.org/pandas-docs/version/0.25.3/reference/api/%s.html",
+        "https://pandas.pydata.org/pandas-docs/stable/reference/api/%s.html",
         "",
     ),
     "pandas_user_guide": (
-        "https://pandas.pydata.org/pandas-docs/version/0.25.3/user_guide/%s.html",
+        "https://pandas.pydata.org/pandas-docs/stable/user_guide/%s.html",
         "Pandas User Guide/",
     ),
     "es_api_docs": (
diff --git a/docs/source/reference/api/eland.Series.isna.rst b/docs/source/reference/api/eland.Series.isna.rst
new file mode 100644
index 00000000..3dcf7b93
--- /dev/null
+++ b/docs/source/reference/api/eland.Series.isna.rst
@@ -0,0 +1,6 @@
+eland.Series.isna
+==================
+
+.. currentmodule:: eland
+
+.. automethod:: Series.isna
diff --git a/docs/source/reference/api/eland.Series.notna.rst b/docs/source/reference/api/eland.Series.notna.rst
new file mode 100644
index 00000000..0167e08e
--- /dev/null
+++ b/docs/source/reference/api/eland.Series.notna.rst
@@ -0,0 +1,6 @@
+eland.Series.notna
+==================
+
+.. currentmodule:: eland
+
+.. automethod:: Series.notna
diff --git a/docs/source/reference/series.rst b/docs/source/reference/series.rst
index 3ab6889a..0c834ec6 100644
--- a/docs/source/reference/series.rst
+++ b/docs/source/reference/series.rst
@@ -74,6 +74,8 @@ Reindexing / selection / label manipulation
    :toctree: api/
 
    Series.rename
+   Series.isna
+   Series.notna
 
 Plotting
 ~~~~~~~~
diff --git a/eland/filter.py b/eland/filter.py
index 2f5800c0..5197cfdf 100644
--- a/eland/filter.py
+++ b/eland/filter.py
@@ -141,7 +141,7 @@ def __init__(self, field: str, value: str) -> None:
 class IsNull(BooleanFilter):
     def __init__(self, field: str) -> None:
         super().__init__()
-        self._filter = {"missing": {"field": field}}
+        self._filter = {"bool": {"must_not": {"exists": {"field": field}}}}
 
 
 class NotNull(BooleanFilter):
diff --git a/eland/series.py b/eland/series.py
index 4343d840..c247f988 100644
--- a/eland/series.py
+++ b/eland/series.py
@@ -39,6 +39,8 @@
     LessEqual,
     ScriptFilter,
     IsIn,
+    IsNull,
+    NotNull,
 )
 
 
@@ -468,6 +470,41 @@ def isin(self, other):
         else:
             raise NotImplementedError(other, type(other))
 
+    def isna(self):
+        """
+        Detect missing values.
+
+        Returns
+        -------
+        eland.Series
+            Mask of bool values for each element in Series that indicates whether an element is not an NA value.
+
+        See Also
+        --------
+        :pandas_api_docs:`pandas.Series.isna`
+        """
+        return IsNull(field=self.name)
+
+    isnull = isna
+
+    def notna(self):
+        """
+        Detect existing (non-missing) values.
+
+        Returns
+        -------
+        eland.Series
+            Mask of bool values for each element in Series that indicates whether an element is not an NA value
+
+        See Also
+        --------
+        :pandas_api_docs:`pandas.Series.notna`
+
+        """
+        return NotNull(field=self.name)
+
+    notnull = notna
+
     @property
     def ndim(self):
         """
diff --git a/eland/tests/operators/test_operators_pytest.py b/eland/tests/operators/test_operators_pytest.py
index 6539de47..ead670e1 100644
--- a/eland/tests/operators/test_operators_pytest.py
+++ b/eland/tests/operators/test_operators_pytest.py
@@ -31,7 +31,7 @@ def test_leaf_boolean_filter(self):
         assert Like("a", "a*b").build() == {"wildcard": {"a": "a*b"}}
         assert Rlike("a", "a*b").build() == {"regexp": {"a": "a*b"}}
         assert Startswith("a", "jj").build() == {"prefix": {"a": "jj"}}
-        assert IsNull("a").build() == {"missing": {"field": "a"}}
+        assert IsNull("a").build() == {"bool": {"must_not": {"exists": {"field": "a"}}}}
         assert NotNull("a").build() == {"exists": {"field": "a"}}
         assert ScriptFilter(
             'doc["num1"].value > params.param1', lang="painless", params={"param1": 5}
diff --git a/eland/tests/series/test_na_pytest.py b/eland/tests/series/test_na_pytest.py
new file mode 100644
index 00000000..7ec9e4e7
--- /dev/null
+++ b/eland/tests/series/test_na_pytest.py
@@ -0,0 +1,44 @@
+# Licensed to Elasticsearch B.V under one or more agreements.
+# Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+# See the LICENSE file in the project root for more information
+
+from eland import eland_to_pandas
+from eland.tests.common import TestData
+from eland.tests.common import assert_pandas_eland_frame_equal
+
+
+class TestSeriesNA(TestData):
+    columns = [
+        "currency",
+        "customer_full_name",
+        "geoip.country_iso_code",
+        "geoip.region_name",
+    ]
+
+    def test_not_isna(self):
+        ed_ecommerce = self.ed_ecommerce()
+        pd_ecommerce = eland_to_pandas(ed_ecommerce)
+
+        for column in self.columns:
+            not_isna_ed_ecommerce = ed_ecommerce[~ed_ecommerce[column].isna()]
+            not_isna_pd_ecommerce = pd_ecommerce[~pd_ecommerce[column].isna()]
+            assert_pandas_eland_frame_equal(
+                not_isna_pd_ecommerce, not_isna_ed_ecommerce
+            )
+
+    def test_isna(self):
+        ed_ecommerce = self.ed_ecommerce()
+        pd_ecommerce = eland_to_pandas(ed_ecommerce)
+
+        isna_ed_ecommerce = ed_ecommerce[ed_ecommerce["geoip.region_name"].isna()]
+        isna_pd_ecommerce = pd_ecommerce[pd_ecommerce["geoip.region_name"].isna()]
+        assert_pandas_eland_frame_equal(isna_pd_ecommerce, isna_ed_ecommerce)
+
+    def test_notna(self):
+        ed_ecommerce = self.ed_ecommerce()
+        pd_ecommerce = eland_to_pandas(ed_ecommerce)
+
+        for column in self.columns:
+            notna_ed_ecommerce = ed_ecommerce[ed_ecommerce[column].notna()]
+            notna_pd_ecommerce = pd_ecommerce[pd_ecommerce[column].notna()]
+            assert_pandas_eland_frame_equal(notna_pd_ecommerce, notna_ed_ecommerce)