diff --git a/src/Makefile.qttest.include b/src/Makefile.qttest.include
--- a/src/Makefile.qttest.include
+++ b/src/Makefile.qttest.include
@@ -14,11 +14,13 @@
 
 if ENABLE_WALLET
 TEST_QT_MOC_CPP += \
+  qt/test/moc_addressbooktests.cpp \
   qt/test/moc_paymentservertests.cpp \
   qt/test/moc_wallettests.cpp
 endif
 
 TEST_QT_H = \
+  qt/test/addressbooktests.h \
   qt/test/bitcoinaddressvalidatortests.h \
   qt/test/compattests.h \
   qt/test/guiutiltests.h \
@@ -51,6 +53,7 @@
   $(TEST_BITCOIN_H)
 if ENABLE_WALLET
 qt_test_test_bitcoin_qt_SOURCES += \
+  qt/test/addressbooktests.cpp \
   qt/test/paymentservertests.cpp \
   qt/test/wallettests.cpp \
   wallet/test/wallet_test_fixture.cpp
diff --git a/src/qt/addressbookpage.h b/src/qt/addressbookpage.h
--- a/src/qt/addressbookpage.h
+++ b/src/qt/addressbookpage.h
@@ -34,7 +34,7 @@
     };
 
     explicit AddressBookPage(const PlatformStyle *platformStyle, Mode mode,
-                             Tabs tab, QWidget *parent);
+                             Tabs tab, QWidget *parent = nullptr);
     ~AddressBookPage();
 
     void setModel(AddressTableModel *model);
diff --git a/src/qt/editaddressdialog.h b/src/qt/editaddressdialog.h
--- a/src/qt/editaddressdialog.h
+++ b/src/qt/editaddressdialog.h
@@ -31,7 +31,7 @@
         EditSendingAddress
     };
 
-    explicit EditAddressDialog(Mode mode, QWidget *parent);
+    explicit EditAddressDialog(Mode mode, QWidget *parent = nullptr);
     ~EditAddressDialog();
 
     void setModel(AddressTableModel *model);
diff --git a/src/qt/test/CMakeLists.txt b/src/qt/test/CMakeLists.txt
--- a/src/qt/test/CMakeLists.txt
+++ b/src/qt/test/CMakeLists.txt
@@ -7,6 +7,7 @@
 add_dependencies(check check-bitcoin-qt)
 
 add_test_to_suite(bitcoin-qt test_bitcoin-qt
+	addressbooktests.cpp
 	bitcoinaddressvalidatortests.cpp
 	compattests.cpp
 	guiutiltests.cpp
diff --git a/src/qt/test/addressbooktests.h b/src/qt/test/addressbooktests.h
new file mode 100644
--- /dev/null
+++ b/src/qt/test/addressbooktests.h
@@ -0,0 +1,14 @@
+#ifndef BITCOIN_QT_TEST_ADDRESSBOOKTESTS_H
+#define BITCOIN_QT_TEST_ADDRESSBOOKTESTS_H
+
+#include <QObject>
+#include <QTest>
+
+class AddressBookTests : public QObject {
+    Q_OBJECT
+
+private Q_SLOTS:
+    void addressBookTests();
+};
+
+#endif // BITCOIN_QT_TEST_ADDRESSBOOKTESTS_H
diff --git a/src/qt/test/addressbooktests.cpp b/src/qt/test/addressbooktests.cpp
new file mode 100644
--- /dev/null
+++ b/src/qt/test/addressbooktests.cpp
@@ -0,0 +1,146 @@
+#include <qt/test/addressbooktests.h>
+#include <test/test_bitcoin.h>
+
+#include <interfaces/node.h>
+#include <qt/addressbookpage.h>
+#include <qt/addresstablemodel.h>
+#include <qt/editaddressdialog.h>
+#include <qt/optionsmodel.h>
+#include <qt/platformstyle.h>
+#include <qt/qvalidatedlineedit.h>
+#include <qt/test/util.h>
+#include <qt/walletmodel.h>
+
+#include <cashaddrenc.h>
+#include <key.h>
+#include <key_io.h>
+#include <pubkey.h>
+#include <wallet/wallet.h>
+
+#include <QMessageBox>
+#include <QTimer>
+
+namespace {
+
+/**
+ * Fill the edit address dialog box with data, submit it, and ensure that
+ * the resulting message meets expectations.
+ */
+void EditAddressAndSubmit(EditAddressDialog *dialog, const QString &label,
+                          const QString &address, QString expected_msg) {
+    QString warning_text;
+
+    dialog->findChild<QLineEdit *>("labelEdit")->setText(label);
+    dialog->findChild<QValidatedLineEdit *>("addressEdit")->setText(address);
+
+    ConfirmMessage(&warning_text, 5);
+    dialog->accept();
+    QCOMPARE(warning_text, expected_msg);
+}
+
+/**
+ * Test adding various send addresses to the address book.
+ *
+ * There are three cases tested:
+ *
+ *   - new_address: a new address which should add as a send address
+ * successfully.
+ *   - existing_s_address: an existing sending address which won't add
+ * successfully.
+ *   - existing_r_address: an existing receiving address which won't add
+ * successfully.
+ *
+ * In each case, verify the resulting state of the address book and optionally
+ * the warning message presented to the user.
+ */
+void TestAddAddressesToSendBook() {
+    TestChain100Setup test;
+    CWallet wallet(Params(), "mock", WalletDatabase::CreateMock());
+    bool firstRun;
+    wallet.LoadWallet(firstRun);
+
+    auto build_address = [&wallet]() {
+        CKey key;
+        key.MakeNewKey(true);
+        CTxDestination dest(GetDestinationForKey(
+            key.GetPubKey(), wallet.m_default_address_type));
+
+        return std::make_pair(
+            dest, QString::fromStdString(EncodeCashAddr(dest, Params())));
+    };
+
+    CTxDestination r_key_dest, s_key_dest;
+
+    // Add a preexisting "receive" entry in the address book.
+    QString preexisting_r_address;
+    QString r_label("already here (r)");
+
+    // Add a preexisting "send" entry in the address book.
+    QString preexisting_s_address;
+    QString s_label("already here (s)");
+
+    // Define a new address (which should add to the address book successfully).
+    QString new_address;
+
+    std::tie(r_key_dest, preexisting_r_address) = build_address();
+    std::tie(s_key_dest, preexisting_s_address) = build_address();
+    std::tie(std::ignore, new_address) = build_address();
+
+    {
+        LOCK(wallet.cs_wallet);
+        wallet.SetAddressBook(r_key_dest, r_label.toStdString(), "receive");
+        wallet.SetAddressBook(s_key_dest, s_label.toStdString(), "send");
+    }
+
+    auto check_addbook_size = [&wallet](int expected_size) {
+        QCOMPARE(static_cast<int>(wallet.mapAddressBook.size()), expected_size);
+    };
+
+    // We should start with the two addresses we added earlier and nothing else.
+    check_addbook_size(2);
+
+    // Initialize relevant QT models.
+    std::unique_ptr<const PlatformStyle> platformStyle(
+        PlatformStyle::instantiate("other"));
+    auto node = interfaces::MakeNode();
+    OptionsModel optionsModel(*node);
+    AddWallet(&wallet);
+    WalletModel walletModel(std::move(node->getWallets()[0]), *node,
+                            platformStyle.get(), &optionsModel);
+    RemoveWallet(&wallet);
+    EditAddressDialog editAddressDialog(EditAddressDialog::NewSendingAddress);
+    editAddressDialog.setModel(walletModel.getAddressTableModel());
+
+    EditAddressAndSubmit(
+        &editAddressDialog, QString("uhoh"), preexisting_r_address,
+        QString(
+            "Address \"%1\" already exists as a receiving address with label "
+            "\"%2\" and so cannot be added as a sending address.")
+            .arg(preexisting_r_address)
+            .arg(r_label));
+
+    check_addbook_size(2);
+
+    EditAddressAndSubmit(
+        &editAddressDialog, QString("uhoh, different"), preexisting_s_address,
+        QString(
+            "The entered address \"%1\" is already in the address book with "
+            "label \"%2\".")
+            .arg(preexisting_s_address)
+            .arg(s_label));
+
+    check_addbook_size(2);
+
+    // Submit a new address which should add successfully - we expect the
+    // warning message to be blank.
+    EditAddressAndSubmit(&editAddressDialog, QString("new"), new_address,
+                         QString(""));
+
+    check_addbook_size(3);
+}
+
+} // namespace
+
+void AddressBookTests::addressBookTests() {
+    TestAddAddressesToSendBook();
+}
diff --git a/src/qt/test/test_main.cpp b/src/qt/test/test_main.cpp
--- a/src/qt/test/test_main.cpp
+++ b/src/qt/test/test_main.cpp
@@ -17,6 +17,7 @@
 #include <qt/test/rpcnestedtests.h>
 #include <qt/test/uritests.h>
 #ifdef ENABLE_WALLET
+#include <qt/test/addressbooktests.h>
 #include <qt/test/paymentservertests.h>
 #include <qt/test/wallettests.h>
 #endif
@@ -104,6 +105,10 @@
     if (QTest::qExec(&test7) != 0) {
         fInvalid = true;
     }
+    AddressBookTests test8;
+    if (QTest::qExec(&test8) != 0) {
+        fInvalid = true;
+    }
 #endif
 
     fs::remove_all(pathTemp);
diff --git a/src/qt/walletmodel.h b/src/qt/walletmodel.h
--- a/src/qt/walletmodel.h
+++ b/src/qt/walletmodel.h
@@ -218,6 +218,10 @@
 
     bool isMultiwallet();
 
+    AddressTableModel *getAddressTableModel() const {
+        return addressTableModel;
+    }
+
 private:
     std::unique_ptr<interfaces::Wallet> m_wallet;
     std::unique_ptr<interfaces::Handler> m_handler_status_changed;