diff --git a/src/Picqer/Financials/Moneybird/Entities/Generic/InvoicePayment.php b/src/Picqer/Financials/Moneybird/Entities/Generic/InvoicePayment.php
new file mode 100644
index 0000000..71d1a9a
--- /dev/null
+++ b/src/Picqer/Financials/Moneybird/Entities/Generic/InvoicePayment.php
@@ -0,0 +1,34 @@
+<?php namespace Picqer\Financials\Moneybird\Entities\Generic;
+
+use Picqer\Financials\Moneybird\Model;
+
+/**
+ * Class InvoicePayment
+ * @package Picqer\Financials\Moneybird\Entities\Generic
+ */
+abstract class InvoicePayment extends Model {
+
+    /**
+     * @var array
+     */
+    protected $fillable = [
+        'id',
+        'invoice_type',
+        'invoice_id',
+        'financial_account_id',
+        'user_id',
+        'payment_transaction_id',
+        'price',
+        'price_base',
+        'payment_date',
+        'credit_invoice_id',
+        'financial_mutation_id',
+        'created_at',
+        'updated_at',
+    ];
+
+    /**
+     * @var string
+     */
+    protected $namespace = 'payment';
+}
\ No newline at end of file
diff --git a/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoice.php b/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoice.php
index 8964729..f128a55 100644
--- a/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoice.php
+++ b/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoice.php
@@ -72,4 +72,26 @@ class PurchaseInvoice extends Model
             'type' => self::NESTING_TYPE_ARRAY_OF_OBJECTS,
         ],
     ];
+
+    /**
+     * Register a payment for the current purchase invoice
+     *
+     * @param PurchaseInvoicePayment $purchaseInvoicePayment (payment_date and price are required)
+     * @throws ApiException
+     */
+    public function registerPayment(PurchaseInvoicePayment $purchaseInvoicePayment)
+    {
+        if  (! isset($purchaseInvoicePayment->payment_date)) {
+            throw new ApiException('Required [payment_date] is missing');
+        }
+
+        if  (! isset($purchaseInvoicePayment->price)) {
+            throw new ApiException('Required [price] is missing');
+        }
+
+        $this->connection()->patch($this->endpoint . '/' . $this->id . '/register_payment',
+            $purchaseInvoicePayment->jsonWithNamespace()
+        );
+    }
+
 }
diff --git a/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoicePayment.php b/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoicePayment.php
new file mode 100644
index 0000000..b6fd25c
--- /dev/null
+++ b/src/Picqer/Financials/Moneybird/Entities/PurchaseInvoicePayment.php
@@ -0,0 +1,11 @@
+<?php namespace Picqer\Financials\Moneybird\Entities;
+
+use Picqer\Financials\Moneybird\Entities\Generic\InvoicePayment;
+
+/**
+ * Class SalesInvoicePayment
+ * @package Picqer\Financials\Moneybird\Entities
+ */
+class PurchaseInvoicePayment extends InvoicePayment
+{
+}
\ No newline at end of file
diff --git a/src/Picqer/Financials/Moneybird/Entities/SalesInvoicePayment.php b/src/Picqer/Financials/Moneybird/Entities/SalesInvoicePayment.php
index d43b2b9..331ee9c 100644
--- a/src/Picqer/Financials/Moneybird/Entities/SalesInvoicePayment.php
+++ b/src/Picqer/Financials/Moneybird/Entities/SalesInvoicePayment.php
@@ -1,34 +1,11 @@
 <?php namespace Picqer\Financials\Moneybird\Entities;
 
-use Picqer\Financials\Moneybird\Model;
+use Picqer\Financials\Moneybird\Entities\Generic\InvoicePayment;
 
 /**
  * Class SalesInvoicePayment
  * @package Picqer\Financials\Moneybird\Entities
  */
-class SalesInvoicePayment extends Model {
-
-    /**
-     * @var array
-     */
-    protected $fillable = [
-        'id',
-        'invoice_type',
-        'invoice_id',
-        'financial_account_id',
-        'user_id',
-        'payment_transaction_id',
-        'price',
-        'price_base',
-        'payment_date',
-        'credit_invoice_id',
-        'financial_mutation_id',
-        'created_at',
-        'updated_at',
-    ];
-
-    /**
-     * @var string
-     */
-    protected $namespace = 'payment';
-}
+class SalesInvoicePayment extends InvoicePayment
+{
+}
\ No newline at end of file
diff --git a/src/Picqer/Financials/Moneybird/Moneybird.php b/src/Picqer/Financials/Moneybird/Moneybird.php
index 43bbf54..70a3627 100644
--- a/src/Picqer/Financials/Moneybird/Moneybird.php
+++ b/src/Picqer/Financials/Moneybird/Moneybird.php
@@ -17,6 +17,7 @@
 use Picqer\Financials\Moneybird\Entities\Product;
 use Picqer\Financials\Moneybird\Entities\PurchaseInvoice;
 use Picqer\Financials\Moneybird\Entities\PurchaseInvoiceDetail;
+use Picqer\Financials\Moneybird\Entities\PurchaseInvoicePayment;
 use Picqer\Financials\Moneybird\Entities\Receipt;
 use Picqer\Financials\Moneybird\Entities\RecurringSalesInvoice;
 use Picqer\Financials\Moneybird\Entities\Note;
@@ -224,6 +225,15 @@ public function purchaseInvoiceDetail($attributes = [])
         return new PurchaseInvoiceDetail($this->connection, $attributes);
     }
 
+    /**
+     * @param array $attributes
+     * @return PurchaseInvoicePayment
+     */
+    public function purchaseInvoicePayment($attributes = [])
+    {
+        return new PurchaseInvoicePayment($this->connection, $attributes);
+    }
+
     /**
      * @param array $attributes
      * @return Receipt