diff --git a/great_tables/_formats.py b/great_tables/_formats.py
index 91157e985..622977a79 100644
--- a/great_tables/_formats.py
+++ b/great_tables/_formats.py
@@ -4601,7 +4601,11 @@ def fmt_nanoplot(
 
     col_class = str(column_d_type).lower()
 
-    if _str_detect(col_class, "int") or _str_detect(col_class, "float"):
+    if (
+        _str_detect(col_class, "int")
+        or _str_detect(col_class, "uint")
+        or _str_detect(col_class, "float")
+    ):
         scalar_vals = True
     else:
         scalar_vals = False
diff --git a/great_tables/_gt_data.py b/great_tables/_gt_data.py
index b166e071c..bfe6d2d4d 100644
--- a/great_tables/_gt_data.py
+++ b/great_tables/_gt_data.py
@@ -379,7 +379,11 @@ def align_from_data(self, data: TblData) -> Self:
                 align.append("left")
             elif col_class == "string":
                 align.append("left")
-            elif _str_detect(col_class, "int") or _str_detect(col_class, "float"):
+            elif (
+                _str_detect(col_class, "int")
+                or _str_detect(col_class, "uint")
+                or _str_detect(col_class, "float")
+            ):
                 align.append("right")
             elif _str_detect(col_class, "date"):
                 align.append("right")
diff --git a/tests/test__boxhead.py b/tests/test__boxhead.py
index 6214948b4..aecd950d3 100644
--- a/tests/test__boxhead.py
+++ b/tests/test__boxhead.py
@@ -99,7 +99,9 @@ def test_cols_align_columns_list_of_str():
 
 
 def test_cols_align_pl_expr():
-    df = pl.DataFrame({"col1": [1, 2], "col2": [3.3, 4.4], "c": ["x", "y"]})
+    df = pl.DataFrame({"col1": [1, 2], "col2": [3.3, 4.4], "c": ["x", "y"]}).with_columns(
+        pl.col("col1").cast(pl.UInt8).alias("d")
+    )
     table = gt.GT(df)
 
     # Select columns by polars expressions
@@ -110,6 +112,7 @@ def test_cols_align_pl_expr():
         "center",  # manually assign
         "center",  # manually assign
         "left",  # `auto_align` for `str` is "left"
+        "right",  # `auto_align` for `pl.UInt` is "right"
     ]
 
 
diff --git a/tests/test_formats.py b/tests/test_formats.py
index 6d0f6ce00..dced11b6f 100644
--- a/tests/test_formats.py
+++ b/tests/test_formats.py
@@ -2236,6 +2236,18 @@ def test_fmt_nanoplot_multi_vals_bar_ref_line_ref_area():
     )
 
 
+def test_fmt_nanoplot_accept_pl_uint():
+    """
+    https://github.com/posit-dev/great-tables/issues/571
+    """
+    single_vals_df = pl.DataFrame({"bars": [1, 2, 3, 5]})
+
+    # Call `as_raw_html()` to trigger `_generate_nanoplot()` and expose the rendering issue.
+    single_vals_df.select("bars").cast(pl.UInt32).style.fmt_nanoplot(
+        columns="bars", plot_type="bar"
+    ).as_raw_html()
+
+
 @pytest.mark.parametrize(
     "plot_type",
     [