diff --git a/electrum/gui/qml/components/InvoiceDialog.qml b/electrum/gui/qml/components/InvoiceDialog.qml
index 59590c622..51f41de5a 100644
--- a/electrum/gui/qml/components/InvoiceDialog.qml
+++ b/electrum/gui/qml/components/InvoiceDialog.qml
@@ -181,7 +181,9 @@ ElDialog {
                                 font.pixelSize: constants.fontSizeXLarge
                                 font.family: FixedFont
                                 font.bold: true
-                                text: Config.formatSats(invoice.amount, false)
+                                text: invoice.invoiceType == Invoice.LightningInvoice
+                                    ? Config.formatMilliSats(invoice.amount, false)
+                                    : Config.formatSats(invoice.amount, false)
                             }
 
                             Label {
@@ -223,12 +225,13 @@ ElDialog {
                                 Layout.preferredWidth: amountFontMetrics.advanceWidth('0') * 14 + leftPadding + rightPadding
                                 fiatfield: amountFiat
                                 readOnly: amountMax.checked
+                                msatPrecision: invoice.invoiceType == Invoice.LightningInvoice
                                 color: readOnly
                                     ? Material.accentColor
                                     : Material.foreground
                                 onTextAsSatsChanged: {
                                     if (!amountMax.checked)
-                                        invoice.amountOverride.satsInt = textAsSats.satsInt
+                                        invoice.amountOverride.copyFrom(textAsSats)
                                 }
                                 Connections {
                                     target: invoice.amountOverride
diff --git a/electrum/gui/qml/components/controls/BtcField.qml b/electrum/gui/qml/components/controls/BtcField.qml
index fca0455fd..a42624356 100644
--- a/electrum/gui/qml/components/controls/BtcField.qml
+++ b/electrum/gui/qml/components/controls/BtcField.qml
@@ -7,12 +7,13 @@ TextField {
     id: amount
 
     required property TextField fiatfield
+    property bool msatPrecision: false
 
     font.family: FixedFont
     placeholderText: qsTr('Amount')
     inputMethodHints: Qt.ImhDigitsOnly
     validator: RegularExpressionValidator {
-        regularExpression: Config.btcAmountRegex
+        regularExpression: msatPrecision ? Config.btcAmountRegexMsat : Config.btcAmountRegex
     }
 
     property Amount textAsSats
diff --git a/electrum/gui/qml/qeinvoice.py b/electrum/gui/qml/qeinvoice.py
index bedc1c659..8e3ce2023 100644
--- a/electrum/gui/qml/qeinvoice.py
+++ b/electrum/gui/qml/qeinvoice.py
@@ -383,7 +383,7 @@ class QEInvoice(QObject, QtEventListener):
         if self.amount.isEmpty:
             if self.amountOverride.isEmpty:
                 raise Exception('can not pay 0 amount')
-            amount_msat = self.amountOverride.satsInt * 1000
+            amount_msat = self.amountOverride.msatsInt
 
         self._wallet.pay_lightning_invoice(self._effectiveInvoice, amount_msat)
 
diff --git a/electrum/gui/qml/qetypes.py b/electrum/gui/qml/qetypes.py
index 090dae9a6..abcb445df 100644
--- a/electrum/gui/qml/qetypes.py
+++ b/electrum/gui/qml/qetypes.py
@@ -90,6 +90,7 @@ class QEAmount(QObject):
         self._is_max = False
         self.valueChanged.emit()
 
+    @pyqtSlot('QVariant')
     def copyFrom(self, amount):
         if not amount:
             self._logger.warning('copyFrom with None argument. assuming 0')  # TODO