diff --git a/src/wp-content/themes/tuleva/helpers/acf/fund-pension.php b/src/wp-content/themes/tuleva/helpers/acf/fund-pension.php
index b3b47a31..35e1ebfc 100644
--- a/src/wp-content/themes/tuleva/helpers/acf/fund-pension.php
+++ b/src/wp-content/themes/tuleva/helpers/acf/fund-pension.php
@@ -52,4 +52,52 @@
     'show_in_rest' => 1,
 ));
 
+acf_add_local_field_group(array (
+    'key' => 'group_fund_pension_sustainability',
+    'title' => 'Sustainability',
+    'fields' => array (
+        array (
+            'key' => 'field_fund_pension_co2_intensity',
+            'label' => 'CO2 Intensity',
+            'name' => 'fund_co2_intensity',
+            // Text, not number: the figure is rendered verbatim and trailing zeros are
+            // significant ("133.80" must not collapse to "133.8"). Matches TKF100's field.
+            'type' => 'text',
+            'instructions' => 'CO2 intensity value (number only, e.g. "83.68"). When set, this replaces the hardcoded figure in the template.',
+            'required' => 0,
+        ),
+    ),
+    'location' => array (
+        array (
+            array (
+                'param' => 'page_template',
+                'operator' => '==',
+                'value' => 'page_fund-stocks.php',
+            ),
+        ),
+        array (
+            array (
+                'param' => 'page_template',
+                'operator' => '==',
+                'value' => 'page_fund-bonds.php',
+            ),
+        ),
+        array (
+            array (
+                'param' => 'page_template',
+                'operator' => '==',
+                'value' => 'page_fund-third.php',
+            ),
+        ),
+    ),
+    'menu_order' => 11,
+    'position' => 'normal',
+    'style' => 'default',
+    'label_placement' => 'top',
+    'instruction_placement' => 'label',
+    'active' => 1,
+    // Same REST requirement as the investment report group above.
+    'show_in_rest' => 1,
+));
+
 endif;
diff --git a/src/wp-content/themes/tuleva/helpers/acf/fund-savings.php b/src/wp-content/themes/tuleva/helpers/acf/fund-savings.php
index fe45c582..b9ad0b09 100644
--- a/src/wp-content/themes/tuleva/helpers/acf/fund-savings.php
+++ b/src/wp-content/themes/tuleva/helpers/acf/fund-savings.php
@@ -176,6 +176,10 @@
     'label_placement' => 'top',
     'instruction_placement' => 'label',
     'active' => 1,
+    // Lets fund_co2_intensity be set over the REST API, the same way the pension funds'
+    // field is. TKF100 has no CO2 figure yet; the template hides the whole block while the
+    // field is empty, so this stays inert until someone supplies a value.
+    'show_in_rest' => 1,
 ));
 
 // Documents fields
diff --git a/src/wp-content/themes/tuleva/templates/components/fund-bonds-details.php b/src/wp-content/themes/tuleva/templates/components/fund-bonds-details.php
index 0d14738f..ec05ee2d 100644
--- a/src/wp-content/themes/tuleva/templates/components/fund-bonds-details.php
+++ b/src/wp-content/themes/tuleva/templates/components/fund-bonds-details.php
@@ -95,7 +95,15 @@
                         <h2 class="mt-5 mb-4 h4"><?php _e('Sustainability information', TEXT_DOMAIN) ?></h2>
                         <p class="fund-info__item">
                             <span class="small text-bold"><?php _e('CO2 intensity', TEXT_DOMAIN) ?></span>
-                            <span><?php echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), '133.80') ?></span>
+                            <span><?php
+                                // The ACF field is the source of truth. The literal below is only
+                                // the pre-ACF value, and renders only while the field is empty.
+                                // Update the field on the page, not this line: editing the literal
+                                // on a fund whose field is already set changes nothing visible,
+                                // which is a quiet way to believe a figure was published.
+                                $co2_intensity = get_field('fund_co2_intensity') ?: '133.80';
+                                echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), esc_html($co2_intensity));
+                            ?></span>
                         </p>
                     </div>
                 </div>
diff --git a/src/wp-content/themes/tuleva/templates/components/fund-stocks-details.php b/src/wp-content/themes/tuleva/templates/components/fund-stocks-details.php
index 5a133b4b..ee1a0fcb 100644
--- a/src/wp-content/themes/tuleva/templates/components/fund-stocks-details.php
+++ b/src/wp-content/themes/tuleva/templates/components/fund-stocks-details.php
@@ -94,7 +94,15 @@
                         <h2 class="mt-5 mb-4 h4"><?php _e('Sustainability information', TEXT_DOMAIN) ?></h2>
                         <p class="fund-info__item">
                             <span class="small text-bold"><?php _e('CO2 intensity', TEXT_DOMAIN) ?></span>
-                            <span><?php echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), 83.68) ?></span>
+                            <span><?php
+                                // The ACF field is the source of truth. The literal below is only
+                                // the pre-ACF value, and renders only while the field is empty.
+                                // Update the field on the page, not this line: editing the literal
+                                // on a fund whose field is already set changes nothing visible,
+                                // which is a quiet way to believe a figure was published.
+                                $co2_intensity = get_field('fund_co2_intensity') ?: '83.68';
+                                echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), esc_html($co2_intensity));
+                            ?></span>
                         </p>
                     </div>
                 </div>
diff --git a/src/wp-content/themes/tuleva/templates/components/fund-third-details.php b/src/wp-content/themes/tuleva/templates/components/fund-third-details.php
index 4f7d2f39..11d65174 100644
--- a/src/wp-content/themes/tuleva/templates/components/fund-third-details.php
+++ b/src/wp-content/themes/tuleva/templates/components/fund-third-details.php
@@ -94,7 +94,15 @@
                         <h2 class="mt-5 mb-4 h4"><?php _e('Sustainability information', TEXT_DOMAIN) ?></h2>
                         <p class="fund-info__item">
                             <span class="small text-bold"><?php _e('CO2 intensity', TEXT_DOMAIN) ?></span>
-                            <span><?php echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), 83.73) ?></span>
+                            <span><?php
+                                // The ACF field is the source of truth. The literal below is only
+                                // the pre-ACF value, and renders only while the field is empty.
+                                // Update the field on the page, not this line: editing the literal
+                                // on a fund whose field is already set changes nothing visible,
+                                // which is a quiet way to believe a figure was published.
+                                $co2_intensity = get_field('fund_co2_intensity') ?: '83.73';
+                                echo sprintf(__('%s tons / $1M turnover per year', TEXT_DOMAIN), esc_html($co2_intensity));
+                            ?></span>
                         </p>
                     </div>
                 </div>