diff --git a/addons/web/static/src/views/fields/datetime/datetime_field.js b/addons/web/static/src/views/fields/datetime/datetime_field.js
index b253bb518bf..42a2b470614 100644
--- a/addons/web/static/src/views/fields/datetime/datetime_field.js
+++ b/addons/web/static/src/views/fields/datetime/datetime_field.js
@@ -40,6 +40,7 @@ export class DateTimeField extends Component {
         endDateField: { type: String, optional: true },
         maxDate: { type: String, optional: true },
         minDate: { type: String, optional: true },
+        alwaysRange: { type: Boolean, optional: true },
         placeholder: { type: String, optional: true },
         required: { type: Boolean, optional: true },
         rounding: { type: Number, optional: true },
@@ -198,7 +199,11 @@ export class DateTimeField extends Component {
         if (!this.relatedField) {
             return false;
         }
-        return this.props.required || ensureArray(value).filter(Boolean).length === 2;
+        return (
+            this.props.alwaysRange ||
+            this.props.required ||
+            ensureArray(value).filter(Boolean).length === 2
+        );
     }
 
     /**
@@ -216,9 +221,10 @@ export class DateTimeField extends Component {
      */
     shouldShowSeparator() {
         return (
-            this.state.range &&
-            (this.props.required ||
-                (!this.isEmpty(this.startDateField) && !this.isEmpty(this.endDateField)))
+            this.props.alwaysRange ||
+            (this.state.range &&
+                (this.props.required ||
+                    (!this.isEmpty(this.startDateField) && !this.isEmpty(this.endDateField))))
         );
     }
 
@@ -275,6 +281,7 @@ export const dateField = {
         endDateField: options[END_DATE_FIELD_OPTION],
         maxDate: options.max_date,
         minDate: options.min_date,
+        alwaysRange: archParseBoolean(options.always_range),
         placeholder: attrs.placeholder,
         required: dynamicInfo.required,
         rounding: options.rounding && parseInt(options.rounding, 10),
@@ -342,6 +349,15 @@ export const dateRangeField = {
             type: "field",
             availableTypes: ["date", "datetime"],
         },
+        {
+            label: _t("Always range"),
+            name: "always_range",
+            type: "boolean",
+            default: false,
+            help: _t(
+                `Set to true the full range input has to be display by default, even if empty.`
+            ),
+        },
     ],
     supportedTypes: ["date", "datetime"],
 };
diff --git a/addons/web/static/src/views/fields/datetime/datetime_field.xml b/addons/web/static/src/views/fields/datetime/datetime_field.xml
index 3dacd40d27f..b702fa41049 100644
--- a/addons/web/static/src/views/fields/datetime/datetime_field.xml
+++ b/addons/web/static/src/views/fields/datetime/datetime_field.xml
@@ -7,7 +7,7 @@
             <t t-if="props.readonly">
                 <span class="text-truncate" t-esc="getFormattedValue(0)" />
             </t>
-            <t t-elif="!props.required and isEmpty(startDateField) and !isEmpty(endDateField)">
+            <t t-elif="!props.required and !props.alwaysRange and isEmpty(startDateField) and !isEmpty(endDateField)">
                 <button
                     class="o_add_date o_add_start_date btn btn-secondary btn-sm w-100"
                     t-on-click="() => this.addDate(0)"
@@ -16,7 +16,7 @@
                     Add start date
                 </button>
             </t>
-            <t t-elif="props.required or !isEmpty(startDateField) or startDateField === props.name">
+            <t t-elif="props.required or props.alwaysRange or !isEmpty(startDateField) or startDateField === props.name">
                 <input
                     t-ref="start-date"
                     type="text"
@@ -44,7 +44,7 @@
                 <t t-if="props.readonly">
                     <span class="text-truncate" t-esc="getFormattedValue(1)" />
                 </t>
-                <t t-elif="!props.required and !isEmpty(startDateField) and isEmpty(endDateField)">
+                <t t-elif="!props.required and !props.alwaysRange and !isEmpty(startDateField) and isEmpty(endDateField)">
                     <button
                         class="o_add_date o_add_end_date btn btn-secondary btn-sm w-100"
                         t-on-click="() => this.addDate(1)"
@@ -53,7 +53,7 @@
                         Add end date
                     </button>
                 </t>
-                <t t-elif="props.required or !isEmpty(endDateField) or endDateField === props.name">
+                <t t-elif="props.required or props.alwaysRange or !isEmpty(endDateField) or endDateField === props.name">
                     <input
                         t-ref="end-date"
                         type="text"
diff --git a/addons/web/static/tests/views/fields/daterange_field_tests.js b/addons/web/static/tests/views/fields/daterange_field_tests.js
index e10a5c4a268..98964c46b12 100644
--- a/addons/web/static/tests/views/fields/daterange_field_tests.js
+++ b/addons/web/static/tests/views/fields/daterange_field_tests.js
@@ -1167,4 +1167,56 @@ QUnit.module("Fields", (hooks) => {
 
         assert.deepEqual(textSiblings, ["->", "02/03/2017"]);
     });
+
+    QUnit.test(
+        "always range: related end date, both start date and end date empty",
+        async (assert) => {
+            serverData.models.partner.records[0].datetime = false;
+
+            await makeView({
+                type: "form",
+                resModel: "partner",
+                serverData,
+                arch: /* xml */ `
+                <form>
+                    <field name="datetime" widget="daterange" options="{'end_date_field': 'datetime_end', 'always_range': '1'}"/>
+                </form>`,
+                resId: 1,
+            });
+
+            assert.strictEqual(getInputs().length, 2);
+            assert.hasAttrValue(getInputs()[0], "data-field", "datetime");
+            assert.strictEqual(getInputs()[0].value, "");
+            assert.hasAttrValue(getInputs()[1], "data-field", "datetime_end");
+            assert.strictEqual(getInputs()[1].value, "");
+            assert.containsNone(target, ".o_add_date");
+
+            await editInput(getInputs()[0], null, "06/06/2023 12:00:00");
+
+            assert.strictEqual(getInputs().length, 2);
+            assert.hasAttrValue(getInputs()[0], "data-field", "datetime");
+            assert.strictEqual(getInputs()[0].value, "06/06/2023 12:00:00");
+            assert.hasAttrValue(getInputs()[1], "data-field", "datetime_end");
+            assert.strictEqual(getInputs()[1].value, "");
+            assert.containsNone(target, ".o_add_date");
+
+            await editInput(getInputs()[1], null, "07/07/2023 13:00:00");
+
+            assert.strictEqual(getInputs().length, 2);
+            assert.hasAttrValue(getInputs()[0], "data-field", "datetime");
+            assert.strictEqual(getInputs()[0].value, "06/06/2023 12:00:00");
+            assert.hasAttrValue(getInputs()[1], "data-field", "datetime_end");
+            assert.strictEqual(getInputs()[1].value, "07/07/2023 13:00:00");
+            assert.containsNone(target, ".o_add_date");
+
+            await editInput(getInputs()[0], null, "");
+
+            assert.strictEqual(getInputs().length, 2);
+            assert.hasAttrValue(getInputs()[0], "data-field", "datetime");
+            assert.strictEqual(getInputs()[0].value, "");
+            assert.hasAttrValue(getInputs()[1], "data-field", "datetime_end");
+            assert.strictEqual(getInputs()[1].value, "07/07/2023 13:00:00");
+            assert.containsNone(target, ".o_add_date");
+        }
+    );
 });