diff --git a/app/src/main/java/com/infomaniak/mail/MatomoMail.kt b/app/src/main/java/com/infomaniak/mail/MatomoMail.kt
index 82ae828b300..8a6c5111437 100644
--- a/app/src/main/java/com/infomaniak/mail/MatomoMail.kt
+++ b/app/src/main/java/com/infomaniak/mail/MatomoMail.kt
@@ -140,6 +140,7 @@ object MatomoMail : Matomo {
         CustomFolder("customFolder"),
         CustomFolders("customFolders"),
         CustomSchedule("customSchedule"),
+        CustomReminder("customReminder"),
         CustomScheduleConfirm("customScheduleConfirm"),
         DailyLimitReachedUpgrade("dailyLimitReachedUpgrade"),
         Delete("delete"),
diff --git a/app/src/main/java/com/infomaniak/mail/ui/alertDialogs/CustomReminderPickerDialog.kt b/app/src/main/java/com/infomaniak/mail/ui/alertDialogs/CustomReminderPickerDialog.kt
new file mode 100644
index 00000000000..f5cabd366c0
--- /dev/null
+++ b/app/src/main/java/com/infomaniak/mail/ui/alertDialogs/CustomReminderPickerDialog.kt
@@ -0,0 +1,124 @@
+/*
+ * Infomaniak Mail - Android
+ * Copyright (C) 2026 Infomaniak Network SA
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.infomaniak.mail.ui.alertDialogs
+
+import android.content.Context
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import com.infomaniak.mail.R
+import com.infomaniak.mail.databinding.DialogCustomReminderPickerBinding
+import com.infomaniak.mail.utils.date.DateFormatUtils.MINUTES_IN_AN_HOUR
+import com.infomaniak.mail.utils.date.DateFormatUtils.MINUTES_IN_A_DAY
+import dagger.hilt.android.qualifiers.ActivityContext
+import dagger.hilt.android.scopes.ActivityScoped
+import javax.inject.Inject
+
+@ActivityScoped
+class CustomReminderPickerDialog @Inject constructor(
+    @ActivityContext private val activityContext: Context,
+) : BaseAlertDialog(activityContext) {
+
+    private val binding: DialogCustomReminderPickerBinding by lazy {
+        DialogCustomReminderPickerBinding.inflate(activity.layoutInflater)
+    }
+
+    override val alertDialog = initDialog()
+
+    private var onDelaySelected: ((Int) -> Unit)? = null
+
+    private val timeUnits = TimeUnit.entries.toTypedArray()
+
+    private fun initDialog() = with(binding) {
+        MaterialAlertDialogBuilder(activityContext)
+            .setTitle(R.string.buttonCustomReminder)
+            .setView(root)
+            .setPositiveButton(R.string.buttonConfirm, null)
+            .setNegativeButton(com.infomaniak.core.legacy.R.string.buttonCancel, null)
+            .create()
+    }
+
+    fun show(onDelaySelected: (Int) -> Unit) {
+        this.onDelaySelected = onDelaySelected
+        alertDialog.show()
+        setupPickers()
+        setupListeners()
+    }
+
+    override fun resetCallbacks() {
+        onDelaySelected = null
+    }
+
+    private fun setupPickers() = with(binding) {
+        numberPicker.minValue = 1
+        numberPicker.maxValue = timeUnits[unitPicker.value].maxValue
+        numberPicker.wrapSelectorWheel = true
+
+        unitPicker.minValue = 0
+        unitPicker.maxValue = timeUnits.size - 1
+        unitPicker.wrapSelectorWheel = false
+
+        updateUnitLabels(numberPicker.value)
+    }
+
+    private fun setupListeners() = with(binding) {
+        numberPicker.setOnValueChangedListener { _, oldVal, newVal ->
+            if ((oldVal == 1 && newVal > 1) || (oldVal > 1 && newVal == 1)) {
+                updateUnitLabels(newVal)
+            }
+        }
+
+        unitPicker.setOnValueChangedListener { _, _, newUnitIndex -> numberPicker.maxValue = timeUnits[newUnitIndex].maxValue }
+
+        positiveButton.setOnClickListener {
+            numberPicker.clearFocus()
+            unitPicker.clearFocus()
+            onDelaySelected?.invoke(getDelayMinutes())
+            alertDialog.dismiss()
+        }
+
+        negativeButton.setOnClickListener { alertDialog.cancel() }
+    }
+
+    private fun updateUnitLabels(currentNumber: Int) {
+        val displayedUnits = timeUnits.map {
+            activityContext.resources.getQuantityString(it.titleRes, currentNumber)
+        }.toTypedArray()
+
+        binding.unitPicker.displayedValues = displayedUnits
+    }
+
+    private fun getDelayMinutes(): Int {
+        val number = binding.numberPicker.value
+        val selectedUnit = timeUnits[binding.unitPicker.value]
+
+        return number * selectedUnit.multiplierInMinutes
+    }
+
+    companion object {
+        private const val MAX_HOURS = 23
+        private const val MAX_DAYS = 30
+
+        enum class TimeUnit(
+            val titleRes: Int,
+            val maxValue: Int,
+            val multiplierInMinutes: Int
+        ) {
+            Hours(R.plurals.unitHours, MAX_HOURS, MINUTES_IN_AN_HOUR),
+            Days(R.plurals.unitDays, MAX_DAYS, MINUTES_IN_A_DAY),
+        }
+    }
+}
diff --git a/app/src/main/java/com/infomaniak/mail/ui/newMessage/sendOptions/DraftSendOptionsFragment.kt b/app/src/main/java/com/infomaniak/mail/ui/newMessage/sendOptions/DraftSendOptionsFragment.kt
index cc97a1dbe53..f983c019073 100644
--- a/app/src/main/java/com/infomaniak/mail/ui/newMessage/sendOptions/DraftSendOptionsFragment.kt
+++ b/app/src/main/java/com/infomaniak/mail/ui/newMessage/sendOptions/DraftSendOptionsFragment.kt
@@ -37,6 +37,7 @@ import com.infomaniak.mail.R
 import com.infomaniak.mail.data.LocalSettings
 import com.infomaniak.mail.data.models.FeatureFlag
 import com.infomaniak.mail.databinding.FragmentSendOptionsBinding
+import com.infomaniak.mail.ui.alertDialogs.CustomReminderPickerDialog
 import com.infomaniak.mail.ui.alertDialogs.SelectDateAndTimeForScheduledDraftDialog
 import com.infomaniak.mail.ui.bottomSheetDialogs.ScheduleOption
 import com.infomaniak.mail.ui.bottomSheetDialogs.ScheduleOptionUtils
@@ -66,6 +67,9 @@ class DraftSendOptionsFragment : Fragment() {
     @Inject
     lateinit var dateAndTimeScheduleDialog: SelectDateAndTimeForScheduledDraftDialog
 
+    @Inject
+    lateinit var customReminderPickerDialog: CustomReminderPickerDialog
+
     @Inject
     lateinit var localSettings: LocalSettings
 
@@ -81,6 +85,7 @@ class DraftSendOptionsFragment : Fragment() {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) = with(binding) {
         dateAndTimeScheduleDialog.bindAlertToLifecycle(viewLifecycleOwner)
+        customReminderPickerDialog.bindAlertToLifecycle(viewLifecycleOwner)
 
         setupScheduleOptions()
         lastScheduleOption.associatedValue = lastSelectedEpoch?.toString()
@@ -372,7 +377,17 @@ class DraftSendOptionsFragment : Fragment() {
     }
 
     private fun showCustomDelayReminderDatePicker() {
-        // TODO
+        customReminderPickerDialog.show(
+            onDelaySelected = { delayMinutes ->
+                trackScheduleSendEvent(MatomoName.CustomReminder)
+                newMessageViewModel.setReminderConfig(ReminderConfig.Delayed(delayMinutes, isCustom = true))
+                binding.customDelayReminder.apply {
+                    setSubtitle(requireContext().formatDelayText(delayMinutes))
+                    setCheckMark(displayCheckMark = true)
+                }
+                binding.optionsDelays.clearCheck()
+            },
+        )
     }
 
 }
diff --git a/app/src/main/res/layout/dialog_custom_reminder_picker.xml b/app/src/main/res/layout/dialog_custom_reminder_picker.xml
new file mode 100644
index 00000000000..aa823ea1f0f
--- /dev/null
+++ b/app/src/main/res/layout/dialog_custom_reminder_picker.xml
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  ~ Infomaniak Mail - Android
+  ~ Copyright (C) 2026 Infomaniak Network SA
+  ~
+  ~ This program is free software: you can redistribute it and/or modify
+  ~ it under the terms of the GNU General Public License as published by
+  ~ the Free Software Foundation, either version 3 of the License, or
+  ~ (at your option) any later version.
+  ~
+  ~ This program is distributed in the hope that it will be useful,
+  ~ but WITHOUT ANY WARRANTY; without even the implied warranty of
+  ~ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  ~ GNU General Public License for more details.
+  ~
+  ~ You should have received a copy of the GNU General Public License
+  ~ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+  -->
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:gravity="center"
+    android:orientation="horizontal"
+    android:paddingHorizontal="@dimen/marginStandard"
+    android:paddingVertical="@dimen/marginStandardSmall">
+
+    <NumberPicker
+        android:id="@+id/numberPicker"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginEnd="@dimen/marginStandardMedium" />
+
+    <NumberPicker
+        android:id="@+id/unitPicker"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content" />
+
+</LinearLayout>
diff --git a/app/src/main/res/values-da/strings.xml b/app/src/main/res/values-da/strings.xml
index 60a3115074c..731bdfdb9d0 100644
--- a/app/src/main/res/values-da/strings.xml
+++ b/app/src/main/res/values-da/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Papirkurv</string>
     <string name="tryAgain">Prøv venligst igen.</string>
     <string name="unblockButton">Fjern blokering</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dag</item>
+        <item quantity="other">Dage</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Time</item>
+        <item quantity="other">Timer</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Ukendt afsender</string>
     <string name="unknownDialogTitleRecipient">Ukendt modtager</string>
     <string name="unknownRecipientTitle">(ukendt)</string>
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index c409fc02c2a..67a0771f300 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Papierkorb</string>
     <string name="tryAgain">Bitte versuchen Sie es erneut.</string>
     <string name="unblockButton">Entsperren</string>
+    <plurals name="unitDays">
+        <item quantity="one">Tag</item>
+        <item quantity="other">Tage</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Stunde</item>
+        <item quantity="other">Stunden</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Unbekannter Spediteur</string>
     <string name="unknownDialogTitleRecipient">Unbekannter Empfänger</string>
     <string name="unknownRecipientTitle">(unbekannt)</string>
diff --git a/app/src/main/res/values-el/strings.xml b/app/src/main/res/values-el/strings.xml
index 125a3139aeb..214c8304b31 100644
--- a/app/src/main/res/values-el/strings.xml
+++ b/app/src/main/res/values-el/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Κάδος απορριμμάτων</string>
     <string name="tryAgain">Παρακαλώ, δοκιμάστε ξανά.</string>
     <string name="unblockButton">Ξεμπλοκάρισμα</string>
+    <plurals name="unitDays">
+        <item quantity="one">Ημέρα</item>
+        <item quantity="other">Ημέρες</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Ώρα</item>
+        <item quantity="other">Ώρες</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Άγνωστος αποστολέας</string>
     <string name="unknownDialogTitleRecipient">Άγνωστος παραλήπτης</string>
     <string name="unknownRecipientTitle">(άγνωστο)</string>
diff --git a/app/src/main/res/values-es/strings.xml b/app/src/main/res/values-es/strings.xml
index 0dace42acdf..df4a38b65b8 100644
--- a/app/src/main/res/values-es/strings.xml
+++ b/app/src/main/res/values-es/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Papelera</string>
     <string name="tryAgain">Por favor, inténtelo de nuevo.</string>
     <string name="unblockButton">Desbloquear</string>
+    <plurals name="unitDays">
+        <item quantity="one">Día</item>
+        <item quantity="other">Días</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Hora</item>
+        <item quantity="other">Horas</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Expedidor desconocido</string>
     <string name="unknownDialogTitleRecipient">Destinatario desconocido</string>
     <string name="unknownRecipientTitle">(desconocido)</string>
diff --git a/app/src/main/res/values-fi/strings.xml b/app/src/main/res/values-fi/strings.xml
index 37245da2bef..efe815aa824 100644
--- a/app/src/main/res/values-fi/strings.xml
+++ b/app/src/main/res/values-fi/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Roskakori</string>
     <string name="tryAgain">Yritä uudelleen.</string>
     <string name="unblockButton">Poista esto</string>
+    <plurals name="unitDays">
+        <item quantity="one">Päivä</item>
+        <item quantity="other">Päivää</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Tunti</item>
+        <item quantity="other">Tuntia</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Tuntematon lähettäjä</string>
     <string name="unknownDialogTitleRecipient">Tuntematon vastaanottaja</string>
     <string name="unknownRecipientTitle">(tuntematon)</string>
diff --git a/app/src/main/res/values-fr/strings.xml b/app/src/main/res/values-fr/strings.xml
index e85db38a77d..aba89e0c3f4 100644
--- a/app/src/main/res/values-fr/strings.xml
+++ b/app/src/main/res/values-fr/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Corbeille</string>
     <string name="tryAgain">Veuillez réessayer.</string>
     <string name="unblockButton">Débloquer</string>
+    <plurals name="unitDays">
+        <item quantity="one">Jour</item>
+        <item quantity="other">Jours</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Heure</item>
+        <item quantity="other">Heures</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Expéditeur inconnu</string>
     <string name="unknownDialogTitleRecipient">Destinataire inconnu</string>
     <string name="unknownRecipientTitle">(inconnu)</string>
diff --git a/app/src/main/res/values-it/strings.xml b/app/src/main/res/values-it/strings.xml
index 5b83a645176..4c59c927a1e 100644
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Cestino</string>
     <string name="tryAgain">Per favore, riprova.</string>
     <string name="unblockButton">Sbloccare</string>
+    <plurals name="unitDays">
+        <item quantity="one">Giorno</item>
+        <item quantity="other">Giorni</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Ora</item>
+        <item quantity="other">Ore</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Spedizioniere sconosciuto</string>
     <string name="unknownDialogTitleRecipient">Destinatario sconosciuto</string>
     <string name="unknownRecipientTitle">(sconosciuto)</string>
diff --git a/app/src/main/res/values-nb/strings.xml b/app/src/main/res/values-nb/strings.xml
index 5a528b9a686..c36ea625582 100644
--- a/app/src/main/res/values-nb/strings.xml
+++ b/app/src/main/res/values-nb/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Papirkurv</string>
     <string name="tryAgain">Vennligst prøv igjen.</string>
     <string name="unblockButton">Opphev blokkering</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dag</item>
+        <item quantity="other">Dager</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Time</item>
+        <item quantity="other">Timer</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Ukjent avsender</string>
     <string name="unknownDialogTitleRecipient">Ukjent mottaker</string>
     <string name="unknownRecipientTitle">(ukjent)</string>
diff --git a/app/src/main/res/values-nl/strings.xml b/app/src/main/res/values-nl/strings.xml
index 270043cdcf8..752b76350e2 100644
--- a/app/src/main/res/values-nl/strings.xml
+++ b/app/src/main/res/values-nl/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Prullenbak</string>
     <string name="tryAgain">Probeer het opnieuw.</string>
     <string name="unblockButton">Deblokkeren</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dag</item>
+        <item quantity="other">Dagen</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Uur</item>
+        <item quantity="other">Uur</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Onbekende afzender</string>
     <string name="unknownDialogTitleRecipient">Onbekende ontvanger</string>
     <string name="unknownRecipientTitle">(onbekend)</string>
diff --git a/app/src/main/res/values-pl/strings.xml b/app/src/main/res/values-pl/strings.xml
index 1ad70767f18..ab3b9449709 100644
--- a/app/src/main/res/values-pl/strings.xml
+++ b/app/src/main/res/values-pl/strings.xml
@@ -787,6 +787,18 @@
     <string name="trashFolder">Kosz</string>
     <string name="tryAgain">Spróbuj ponownie.</string>
     <string name="unblockButton">Odblokuj</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dzień</item>
+        <item quantity="few">Dni</item>
+        <item quantity="many">Dni</item>
+        <item quantity="other">Dni</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Godzina</item>
+        <item quantity="few">Godziny</item>
+        <item quantity="many">Godzin</item>
+        <item quantity="other">Godzin</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Nieznany nadawca</string>
     <string name="unknownDialogTitleRecipient">Nieznany odbiorca</string>
     <string name="unknownRecipientTitle">(nieznany)</string>
diff --git a/app/src/main/res/values-pt/strings.xml b/app/src/main/res/values-pt/strings.xml
index 9a15d48785b..c5ebcab3003 100644
--- a/app/src/main/res/values-pt/strings.xml
+++ b/app/src/main/res/values-pt/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Lixo</string>
     <string name="tryAgain">Por favor, tente novamente.</string>
     <string name="unblockButton">Desbloquear</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dia</item>
+        <item quantity="other">Dias</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Hora</item>
+        <item quantity="other">Horas</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Remetente desconhecido</string>
     <string name="unknownDialogTitleRecipient">Destinatário desconhecido</string>
     <string name="unknownRecipientTitle">(desconhecido)</string>
diff --git a/app/src/main/res/values-sv/strings.xml b/app/src/main/res/values-sv/strings.xml
index fd038232252..1f2c14f8d51 100644
--- a/app/src/main/res/values-sv/strings.xml
+++ b/app/src/main/res/values-sv/strings.xml
@@ -729,6 +729,14 @@
     <string name="trashFolder">Papperskorg</string>
     <string name="tryAgain">Försök igen.</string>
     <string name="unblockButton">Avblockera</string>
+    <plurals name="unitDays">
+        <item quantity="one">Dag</item>
+        <item quantity="other">Dagar</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Timme</item>
+        <item quantity="other">Timmar</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Okänd avsändare</string>
     <string name="unknownDialogTitleRecipient">Okänd mottagare</string>
     <string name="unknownRecipientTitle">(okänd)</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index e5ed9286206..4df26952dfa 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -733,6 +733,14 @@
     <string name="trashFolder">Trash</string>
     <string name="tryAgain">Please try again.</string>
     <string name="unblockButton">Unblock</string>
+    <plurals name="unitDays">
+        <item quantity="one">Day</item>
+        <item quantity="other">Days</item>
+    </plurals>
+    <plurals name="unitHours">
+        <item quantity="one">Hour</item>
+        <item quantity="other">Hours</item>
+    </plurals>
     <string name="unknownDialogTitleExpeditor">Unknown expeditor</string>
     <string name="unknownDialogTitleRecipient">Unknown recipient</string>
     <string name="unknownRecipientTitle">(unknown)</string>