diff --git a/CHANGES b/CHANGES
index ad91f5ac..8fa61fad 100644
--- a/CHANGES
+++ b/CHANGES
@@ -27,6 +27,10 @@ Fixes
     there are no spaces around the equal sign (issue #272, PR #273).    
   - Pre-processing function slicing will not drop NaN rows (issue
     #274, PR #275).
+    
+Deprecations
+  - deprecate AutoMBAR for removal in 2.0 because pymbar 4 already contains
+    equivalent functionality (issue #284, PR #285).
 
 Internal Enhancements (do not affect API)
   - Blackfy the codebase (PR #280).
diff --git a/src/alchemlyb/estimators/mbar_.py b/src/alchemlyb/estimators/mbar_.py
index 4759d687..001e85b9 100644
--- a/src/alchemlyb/estimators/mbar_.py
+++ b/src/alchemlyb/estimators/mbar_.py
@@ -1,4 +1,5 @@
 import logging
+from warnings import warn
 
 import pandas as pd
 import pymbar
@@ -200,6 +201,9 @@ class AutoMBAR(MBAR):
     .. versionadded:: 0.6.0
     .. versionchanged:: 1.0.0
        AutoMBAR accepts the `method` argument.
+    .. deprecated:: 1.0.1
+       Deprecate AutoMBAR in favour of MBAR for pymbar4. It will be removed
+       in alchemlyb 2.0.0.
     """
 
     def __init__(
@@ -210,6 +214,10 @@ def __init__(
         verbose=False,
         method=None,
     ):
+        warn(
+            "From version 2.0.0, this will be replaced by the default alchemlyb.estimators.MBAR.",
+            DeprecationWarning,
+        )
         super().__init__(
             maximum_iterations=maximum_iterations,
             relative_tolerance=relative_tolerance,
diff --git a/src/alchemlyb/tests/pytest.ini b/src/alchemlyb/tests/pytest.ini
new file mode 100644
index 00000000..fa6b641f
--- /dev/null
+++ b/src/alchemlyb/tests/pytest.ini
@@ -0,0 +1,3 @@
+[pytest]
+filterwarnings =
+    ignore:From version 2.0.0, this will be replaced by the default alchemlyb.estimators.MBAR.:DeprecationWarning:
\ No newline at end of file
diff --git a/src/alchemlyb/tests/test_fep_estimators.py b/src/alchemlyb/tests/test_fep_estimators.py
index 9d041eb8..c6d8e4b7 100644
--- a/src/alchemlyb/tests/test_fep_estimators.py
+++ b/src/alchemlyb/tests/test_fep_estimators.py
@@ -55,6 +55,10 @@ def test_mbar(self, X_delta_f):
 class TestAutoMBAR(TestMBAR):
     cls = AutoMBAR
 
+    def test_autombar(self, X_delta_f):
+        with pytest.deprecated_call():
+            self.compare_delta_f(X_delta_f)
+
 
 class TestMBAR_fail:
     def test_failback_adaptive(self, gmx_ABFE_complex_n_uk):