diff --git a/blocks/blocks.py b/blocks/blocks.py
index 63b6676c..6dc40de1 100644
--- a/blocks/blocks.py
+++ b/blocks/blocks.py
@@ -1,5 +1,5 @@
-from django.core.validators import validate_slug
 from django import forms
+from django.core.validators import validate_slug
 from django.forms.utils import flatatt
 from django.utils.html import format_html, format_html_join
 from wagtail import blocks as wagtail_blocks
@@ -44,6 +44,10 @@ class Meta:
 
 class FormattedImageChooserStructBlock(wagtail_blocks.StructBlock):
     image = ImageChooserBlock()
+    caption = wagtail_blocks.CharBlock(
+        required=False,
+        help_text="Optional caption (tooltip) to display with the image.",
+    )
     width = wagtail_blocks.IntegerBlock(
         min_value=0,
         max_value=800,
diff --git a/blocks/templates/blocks/blocks/formatted_image_block.html b/blocks/templates/blocks/blocks/formatted_image_block.html
index ea22b830..4f6acb96 100644
--- a/blocks/templates/blocks/blocks/formatted_image_block.html
+++ b/blocks/templates/blocks/blocks/formatted_image_block.html
@@ -8,6 +8,10 @@
 <img
     src="{{ block_image.url }}"
     width="{{ value.width }}"
+    {% if value.caption %}
+        title="{{ value.caption }}"
+        alt="{{ value.caption }}"
+    {% endif %}
     {% if value.align == "right" %}
         class="richtext-image right"
     {% elif value.align == "left" %}