diff --git a/src/govuk/components/summary-list/_index.scss b/src/govuk/components/summary-list/_index.scss
index 3e9b60ac5d..6604056eee 100644
--- a/src/govuk/components/summary-list/_index.scss
+++ b/src/govuk/components/summary-list/_index.scss
@@ -6,15 +6,17 @@
       display: table;
       width: 100%;
       table-layout: fixed; // Required to allow us to wrap words that overflow.
+      border-collapse: collapse;
     }
     margin: 0; // Reset default user agent styles
     @include govuk-responsive-margin(6, "bottom");
   }
 
   .govuk-summary-list__row {
+    border-bottom: 1px solid $govuk-border-colour;
+
     @include govuk-media-query($until: tablet) {
       margin-bottom: govuk-spacing(3);
-      border-bottom: 1px solid $govuk-border-colour;
     }
     @include govuk-media-query($from: tablet) {
       display: table-row;
@@ -31,7 +33,6 @@
       padding-top: govuk-spacing(2);
       padding-right: govuk-spacing(4);
       padding-bottom: govuk-spacing(2);
-      border-bottom: 1px solid $govuk-border-colour;
     }
   }
 
@@ -109,37 +110,25 @@
 
   // No border on entire summary list
   .govuk-summary-list--no-border {
-    @include govuk-media-query($until: tablet) {
-      .govuk-summary-list__row {
-        border: 0;
-      }
+    .govuk-summary-list__row {
+      border: 0;
     }
 
-    @include govuk-media-query($from: tablet) {
-      .govuk-summary-list__key,
-      .govuk-summary-list__value,
-      .govuk-summary-list__actions {
-        // Remove 1px border, add 1px height back on
-        padding-bottom: govuk-spacing(2) + 1px;
-        border: 0;
-      }
+    .govuk-summary-list__key,
+    .govuk-summary-list__value,
+    .govuk-summary-list__actions {
+      padding-bottom: govuk-spacing(2) + 1px;
     }
   }
 
   // No border on specific rows
   .govuk-summary-list__row--no-border {
-    @include govuk-media-query($until: tablet) {
-      border: 0;
-    }
+    border: 0;
 
-    @include govuk-media-query($from: tablet) {
-      .govuk-summary-list__key,
-      .govuk-summary-list__value,
-      .govuk-summary-list__actions {
-        // Remove 1px border, add 1px height back on
-        padding-bottom: govuk-spacing(2) + 1px;
-        border: 0;
-      }
+    .govuk-summary-list__key,
+    .govuk-summary-list__value,
+    .govuk-summary-list__actions {
+      padding-bottom: govuk-spacing(2) + 1px;
     }
   }
 }
diff --git a/src/govuk/components/summary-list/template.njk b/src/govuk/components/summary-list/template.njk
index 8434378922..8319330002 100644
--- a/src/govuk/components/summary-list/template.njk
+++ b/src/govuk/components/summary-list/template.njk
@@ -7,12 +7,6 @@
   </a>
 {% endmacro -%}
 
-{# Determine if we need 2 or 3 columns #}
-{% set anyRowHasActions = false %}
-{% for row in params.rows %}
-  {% set anyRowHasActions = true if row.actions.items | length else anyRowHasActions %}
-{% endfor -%}
-
 <dl class="govuk-summary-list {%- if params.classes %} {{ params.classes }}{% endif %}"{% for attribute, value in params.attributes %} {{attribute}}="{{value}}"{% endfor %}>
   {% for row in params.rows %}
     {% if row %}
@@ -37,9 +31,6 @@
               </ul>
             {% endif %}
           </dd>
-        {% elseif anyRowHasActions %}
-          {# Add dummy column to extend border #}
-          <span class="govuk-summary-list__actions"></span>
         {% endif %}
       </div>
     {% endif %}
diff --git a/src/govuk/components/summary-list/template.test.js b/src/govuk/components/summary-list/template.test.js
index 8e1b69e4ee..8343ef2b48 100644
--- a/src/govuk/components/summary-list/template.test.js
+++ b/src/govuk/components/summary-list/template.test.js
@@ -216,21 +216,6 @@ describe('Summary list', () => {
 
         expect($action.length).toEqual(0)
       })
-
-      it('adds dummy action columns when only some rows have actions', async () => {
-        const $ = render('summary-list', examples['with some actions'])
-
-        const $component = $('.govuk-summary-list')
-        const $action = $component.find('.govuk-summary-list__actions')
-
-        // First action column contains link text
-        expect($action[0].tagName).toEqual('dd')
-        expect($($action[0]).text()).toContain('Edit')
-
-        // Second action column is a dummy
-        expect($action[1].tagName).toEqual('span')
-        expect($($action[1]).text()).toEqual('')
-      })
     })
   })
 })