diff --git a/docs/_static/anymail-theme.css b/docs/_static/anymail-theme.css
index 215cf2a..a84e62b 100644
--- a/docs/_static/anymail-theme.css
+++ b/docs/_static/anymail-theme.css
@@ -19,3 +19,23 @@
     -webkit-user-select: none;
     -ms-user-select: none;
 }
+
+
+/* Sticky table first column (used for ESP feature matrix) */
+table.sticky-left td:first-of-type,
+table.sticky-left th:first-of-type {
+    position: -webkit-sticky; /* Safari */
+    position: sticky;
+    left: 0;
+    background-color: #fcfcfc; /* override transparent from .wy-table td */
+}
+table.sticky-left td:first-of-type[colspan] > p,
+table.sticky-left th:first-of-type[colspan] > p {
+    /* Hack: the full-width <td colspan=N> section headers can't stick left;
+       since those always wrap a rubric <p> (in the specific table that uses this),
+       just make the <p> sticky within the <td>. */
+    display: inline-block;
+    position: -webkit-sticky; /* Safari */
+    position: sticky;
+    left: 17px; /* (.wy-table $table-padding-size) + (docutils border="1" in html) */
+}
diff --git a/docs/esps/index.rst b/docs/esps/index.rst
index 3e979ce..abb908a 100644
--- a/docs/esps/index.rst
+++ b/docs/esps/index.rst
@@ -28,6 +28,8 @@ The table below summarizes the Anymail features supported for each ESP.
 
 .. currentmodule:: anymail.message
 
+.. rst-class:: sticky-left
+
 ============================================  ===========  ==========  ===========  ==========  ==========  ============  ===========
 Email Service Provider                        |Mailgun|    |Mailjet|   |Mandrill|   |Postmark|  |SendGrid|  |SendinBlue|  |SparkPost|
 ============================================  ===========  ==========  ===========  ==========  ==========  ============  ===========