diff --git a/packages/server/src/interfaces/SaleInvoice.ts b/packages/server/src/interfaces/SaleInvoice.ts
index 394319e86..61594306a 100644
--- a/packages/server/src/interfaces/SaleInvoice.ts
+++ b/packages/server/src/interfaces/SaleInvoice.ts
@@ -201,3 +201,15 @@ export interface ISaleInvoiceNotifyPayload {
   saleInvoiceId: number;
   messageDTO: SendInvoiceMailDTO;
 }
+
+export interface ISaleInvoiceMailSend {
+  tenantId: number;
+  saleInvoiceId: number;
+  messageOptions: SendInvoiceMailDTO;
+}
+
+export interface ISaleInvoiceMailSent {
+  tenantId: number;
+  saleInvoiceId: number;
+  messageOptions: SendInvoiceMailDTO;
+}
diff --git a/packages/server/src/loaders/eventEmitter.ts b/packages/server/src/loaders/eventEmitter.ts
index fa1942b72..5e052f376 100644
--- a/packages/server/src/loaders/eventEmitter.ts
+++ b/packages/server/src/loaders/eventEmitter.ts
@@ -84,6 +84,7 @@ import { WriteInvoiceTaxTransactionsSubscriber } from '@/services/TaxRates/subsc
 import { BillTaxRateValidateSubscriber } from '@/services/TaxRates/subscribers/BillTaxRateValidateSubscriber';
 import { WriteBillTaxTransactionsSubscriber } from '@/services/TaxRates/subscribers/WriteBillTaxTransactionsSubscriber';
 import { SyncItemTaxRateOnEditTaxSubscriber } from '@/services/TaxRates/SyncItemTaxRateOnEditTaxSubscriber';
+import { InvoiceChangeStatusOnMailSentSubscriber } from '@/services/Sales/Invoices/subscribers/InvoiceChangeStatusOnMailSentSubscriber';
 
 export default () => {
   return new EventPublisher();
@@ -152,6 +153,7 @@ export const susbcribers = () => {
     // #Invoices
     InvoicePaymentGLRewriteSubscriber,
     InvoiceCostGLEntriesSubscriber,
+    InvoiceChangeStatusOnMailSentSubscriber,
 
     BillPaymentsGLEntriesRewriteSubscriber,
 
diff --git a/packages/server/src/services/Sales/Invoices/DeliverSaleInvoice.ts b/packages/server/src/services/Sales/Invoices/DeliverSaleInvoice.ts
index 30ba635a6..f5500a03a 100644
--- a/packages/server/src/services/Sales/Invoices/DeliverSaleInvoice.ts
+++ b/packages/server/src/services/Sales/Invoices/DeliverSaleInvoice.ts
@@ -4,7 +4,6 @@ import { ServiceError } from '@/exceptions';
 import {
   ISaleInvoiceDeliveringPayload,
   ISaleInvoiceEventDeliveredPayload,
-  ISystemUser,
 } from '@/interfaces';
 import { ERRORS } from './constants';
 import { Inject, Service } from 'typedi';
@@ -36,8 +35,7 @@ export class DeliverSaleInvoice {
    */
   public async deliverSaleInvoice(
     tenantId: number,
-    saleInvoiceId: number,
-    authorizedUser: ISystemUser
+    saleInvoiceId: number
   ): Promise<void> {
     const { SaleInvoice } = this.tenancy.models(tenantId);
 
diff --git a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMail.ts b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMail.ts
index 05db4f73e..eff8b2603 100644
--- a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMail.ts
+++ b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMail.ts
@@ -1,6 +1,6 @@
 import { Inject, Service } from 'typedi';
 import Mail from '@/lib/Mail';
-import { SendInvoiceMailDTO } from '@/interfaces';
+import { ISaleInvoiceMailSend, SendInvoiceMailDTO } from '@/interfaces';
 import { SaleInvoicePdf } from './SaleInvoicePdf';
 import { SendSaleInvoiceMailCommon } from './SendInvoiceInvoiceMailCommon';
 import {
@@ -8,6 +8,8 @@ import {
   DEFAULT_INVOICE_MAIL_SUBJECT,
 } from './constants';
 import { parseAndValidateMailOptions } from '@/services/MailNotification/utils';
+import events from '@/subscribers/events';
+import { EventPublisher } from '@/lib/EventPublisher/EventPublisher';
 
 @Service()
 export class SendSaleInvoiceMail {
@@ -20,6 +22,9 @@ export class SendSaleInvoiceMail {
   @Inject('agenda')
   private agenda: any;
 
+  @Inject()
+  private eventPublisher: EventPublisher;
+
   /**
    * Sends the invoice mail of the given sale invoice.
    * @param {number} tenantId
@@ -29,14 +34,21 @@ export class SendSaleInvoiceMail {
   public async triggerMail(
     tenantId: number,
     saleInvoiceId: number,
-    messageDTO: SendInvoiceMailDTO
+    messageOptions: SendInvoiceMailDTO
   ) {
     const payload = {
       tenantId,
       saleInvoiceId,
-      messageDTO,
+      messageOptions,
     };
     await this.agenda.now('sale-invoice-mail-send', payload);
+
+    // Triggers the event `onSaleInvoicePreMailSend`.
+    await this.eventPublisher.emitAsync(events.saleInvoice.onPreMailSend, {
+      tenantId,
+      saleInvoiceId,
+      messageOptions,
+    } as ISaleInvoiceMailSend);
   }
 
   /**
@@ -64,7 +76,7 @@ export class SendSaleInvoiceMail {
   public async sendMail(
     tenantId: number,
     saleInvoiceId: number,
-    messageDTO: SendInvoiceMailDTO
+    messageOptions: SendInvoiceMailDTO
   ) {
     const defaultMessageOpts = await this.getMailOption(
       tenantId,
@@ -73,7 +85,7 @@ export class SendSaleInvoiceMail {
     // Merge message opts with default options and validate the incoming options.
     const messageOpts = parseAndValidateMailOptions(
       defaultMessageOpts,
-      messageDTO
+      messageOptions
     );
     const mail = new Mail()
       .setSubject(messageOpts.subject)
@@ -90,6 +102,20 @@ export class SendSaleInvoiceMail {
         { filename: 'invoice.pdf', content: invoicePdfBuffer },
       ]);
     }
+    // Triggers the event `onSaleInvoiceSend`.
+    await this.eventPublisher.emitAsync(events.saleInvoice.onMailSend, {
+      tenantId,
+      saleInvoiceId,
+      messageOptions,
+    } as ISaleInvoiceMailSend);
+
     await mail.send();
+
+    // Triggers the event `onSaleInvoiceSend`.
+    await this.eventPublisher.emitAsync(events.saleInvoice.onMailSent, {
+      tenantId,
+      saleInvoiceId,
+      messageOptions,
+    } as ISaleInvoiceMailSend);
   }
 }
diff --git a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailJob.ts b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailJob.ts
index 3c1e49a6c..9de941f5f 100644
--- a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailJob.ts
+++ b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailJob.ts
@@ -19,11 +19,11 @@ export class SendSaleInvoiceMailJob {
    * Triggers sending invoice mail.
    */
   private handler = async (job, done: Function) => {
-    const { tenantId, saleInvoiceId, messageDTO } = job.attrs.data;
+    const { tenantId, saleInvoiceId, messageOptions } = job.attrs.data;
     const sendInvoiceMail = Container.get(SendSaleInvoiceMail);
 
     try {
-      await sendInvoiceMail.sendMail(tenantId, saleInvoiceId, messageDTO);
+      await sendInvoiceMail.sendMail(tenantId, saleInvoiceId, messageOptions);
       done();
     } catch (error) {
       console.log(error);
diff --git a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailReminder.ts b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailReminder.ts
index f16db0172..7829a3bf2 100644
--- a/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailReminder.ts
+++ b/packages/server/src/services/Sales/Invoices/SendSaleInvoiceMailReminder.ts
@@ -1,5 +1,9 @@
 import { Inject, Service } from 'typedi';
-import { SendInvoiceMailDTO } from '@/interfaces';
+import {
+  ISaleInvoiceMailSend,
+  ISaleInvoiceMailSent,
+  SendInvoiceMailDTO,
+} from '@/interfaces';
 import Mail from '@/lib/Mail';
 import { SaleInvoicePdf } from './SaleInvoicePdf';
 import { SendSaleInvoiceMailCommon } from './SendInvoiceInvoiceMailCommon';
@@ -8,6 +12,8 @@ import {
   DEFAULT_INVOICE_REMINDER_MAIL_SUBJECT,
 } from './constants';
 import { parseAndValidateMailOptions } from '@/services/MailNotification/utils';
+import { EventPublisher } from '@/lib/EventPublisher/EventPublisher';
+import events from '@/subscribers/events';
 
 @Service()
 export class SendInvoiceMailReminder {
@@ -20,6 +26,9 @@ export class SendInvoiceMailReminder {
   @Inject()
   private invoiceCommonMail: SendSaleInvoiceMailCommon;
 
+  @Inject()
+  private eventPublisher: EventPublisher;
+
   /**
    * Triggers the reminder mail of the given sale invoice.
    * @param {number} tenantId
@@ -86,6 +95,18 @@ export class SendInvoiceMailReminder {
         { filename: 'invoice.pdf', content: invoicePdfBuffer },
       ]);
     }
+    // Triggers the event `onSaleInvoiceSend`.
+    await this.eventPublisher.emitAsync(events.saleInvoice.onMailReminderSend, {
+      saleInvoiceId,
+      messageOptions,
+    } as ISaleInvoiceMailSend);
+
     await mail.send();
+
+    // Triggers the event `onSaleInvoiceSent`.
+    await this.eventPublisher.emitAsync(events.saleInvoice.onMailReminderSent, {
+      saleInvoiceId,
+      messageOptions,
+    } as ISaleInvoiceMailSent);
   }
 }
diff --git a/packages/server/src/services/Sales/Invoices/subscribers/InvoiceChangeStatusOnMailSentSubscriber.ts b/packages/server/src/services/Sales/Invoices/subscribers/InvoiceChangeStatusOnMailSentSubscriber.ts
new file mode 100644
index 000000000..fc4392777
--- /dev/null
+++ b/packages/server/src/services/Sales/Invoices/subscribers/InvoiceChangeStatusOnMailSentSubscriber.ts
@@ -0,0 +1,49 @@
+import { Inject, Service } from 'typedi';
+import events from '@/subscribers/events';
+import { ISaleInvoiceMailSent } from '@/interfaces';
+import { DeliverSaleInvoice } from '../DeliverSaleInvoice';
+import { ServiceError } from '@/exceptions';
+import { ERRORS } from '../constants';
+
+@Service()
+export class InvoiceChangeStatusOnMailSentSubscriber {
+  @Inject()
+  private markInvoiceDelivedService: DeliverSaleInvoice;
+
+  /**
+   * Attaches events.
+   */
+  public attach(bus) {
+    bus.subscribe(events.saleInvoice.onPreMailSend, this.markInvoiceDelivered);
+    bus.subscribe(
+      events.saleInvoice.onMailReminderSent,
+      this.markInvoiceDelivered
+    );
+  }
+
+  /**
+   * Marks the invoice delivered once the invoice mail sent.
+   * @param {ISaleInvoiceMailSent}
+   * @returns {Promise<void>}
+   */
+  private markInvoiceDelivered = async ({
+    tenantId,
+    saleInvoiceId,
+    messageOptions,
+  }: ISaleInvoiceMailSent) => {
+    try {
+      await this.markInvoiceDelivedService.deliverSaleInvoice(
+        tenantId,
+        saleInvoiceId
+      );
+    } catch (error) {
+      if (
+        error instanceof ServiceError &&
+        error.errorType === ERRORS.SALE_INVOICE_ALREADY_DELIVERED
+      ) {
+      } else {
+        throw error;
+      }
+    }
+  };
+}
diff --git a/packages/server/src/subscribers/events.ts b/packages/server/src/subscribers/events.ts
index e54f48152..a46c32696 100644
--- a/packages/server/src/subscribers/events.ts
+++ b/packages/server/src/subscribers/events.ts
@@ -131,7 +131,14 @@ export default {
     onNotifiedSms: 'onSaleInvoiceNotifiedSms',
 
     onNotifyMail: 'onSaleInvoiceNotifyMail',
-    onNotifyReminderMail: 'onSaleInvoiceNotifyReminderMail'
+    onNotifyReminderMail: 'onSaleInvoiceNotifyReminderMail',
+
+    onPreMailSend: 'onSaleInvoicePreMailSend',
+    onMailSend: 'onSaleInvoiceMailSend',
+    onMailSent: 'onSaleInvoiceMailSent',
+
+    onMailReminderSend: 'onSaleInvoiceMailReminderSend',
+    onMailReminderSent: 'onSaleInvoiceMailReminderSent',
   },
 
   /**
@@ -164,7 +171,7 @@ export default {
     onRejecting: 'onSaleEstimateRejecting',
     onRejected: 'onSaleEstimateRejected',
 
-    onNotifyMail: 'onSaleEstimateNotifyMail'
+    onNotifyMail: 'onSaleEstimateNotifyMail',
   },
 
   /**
@@ -580,6 +587,6 @@ export default {
     onActivated: 'onTaxRateActivated',
 
     onInactivating: 'onTaxRateInactivating',
-    onInactivated: 'onTaxRateInactivated'
+    onInactivated: 'onTaxRateInactivated',
   },
 };