diff --git a/CHANGELOG-2.0.md b/CHANGELOG-2.0.md
index c68dbd6f..ebe388c4 100644
--- a/CHANGELOG-2.0.md
+++ b/CHANGELOG-2.0.md
@@ -1,5 +1,9 @@
 # CHANGELOG
 
+### v2.0.3 (2025-10-31)
+
+- [#400](https://github.com/Sylius/InvoicingPlugin/pull/400) Fix InvoiceLineItem net price calculator ([@tomkalon](https://github.com/tomkalon))
+
 ### v2.0.2 (2025-07-03)
 
 - [#373](https://github.com/Sylius/InvoicingPlugin/pull/373) Add sylius/test-application ([@Wojdylak](https://github.com/Wojdylak))
diff --git a/UPGRADE-2.0.md b/UPGRADE-2.0.md
index 052c0a91..a980437a 100644
--- a/UPGRADE-2.0.md
+++ b/UPGRADE-2.0.md
@@ -1,3 +1,31 @@
+# UPGRADE FROM 2.0.2 TO 2.0.3
+
+### Deprecations
+- `Sylius\InvoicingPlugin\Provider\UnitNetPriceProvider` — **deprecated since 2.0** and will be removed in 3.0. 
+- The `orderItemUnitsToLineItemsConverter` argument and property in `Sylius\InvoicingPlugin\Generator\InvoiceGenerator` — **deprecated since 2.0.3**, to be removed in 3.0.
+- Using `InvoiceGenerator` without providing `orderItemsToLineItemsConverter` is **deprecated since 2.0** and will become an error in 3.0.
+
+```diff
+<service id="sylius_invoicing.generator.invoice" class="Sylius\InvoicingPlugin\Generator\InvoiceGenerator">
+    <argument type="service" id="sylius_invoicing.generator.invoice_identifier" />
+    <argument type="service" id="sylius_invoicing.generator.invoice_number" />
+    <argument type="service" id="sylius_invoicing.custom_factory.invoice" />
+    <argument type="service" id="sylius_invoicing.factory.billing_data" />
+    <argument type="service" id="sylius_invoicing.factory.shop_billing_data" />
+    <argument type="service" id="sylius_invoicing.converter.order_item_units_to_line_items" />
+    <argument type="service" id="sylius_invoicing.converter.shipping_adjustments_to_line_items" />
+    <argument type="service" id="sylius_invoicing.converter.tax_items" />
++   <argument type="service" id="sylius_invoicing.converter.order_item_to_line_items" />
+</service>
+```
+
+### Changed
+- `InvoiceGenerator` now prefers `orderItemsToLineItemsConverter`; if it is not provided, it falls back to the (deprecated) `orderItemUnitsToLineItemsConverter` and emits deprecation warnings.
+
+### Removed (since 3.0)
+- `UnitNetPriceProvider`
+- `orderItemUnitsToLineItemsConverter` from `InvoiceGenerator` (argument and property)
+
 # UPGRADE FROM 1.X TO 2.0
 
 1. Support for Sylius 2.0 has been added, it is now the recommended Sylius version to use with InvoicingPlugin.
diff --git a/config/services.xml b/config/services.xml
index 47ea616a..ae39c664 100644
--- a/config/services.xml
+++ b/config/services.xml
@@ -73,5 +73,10 @@
             class="Sylius\InvoicingPlugin\Provider\UnitNetPriceProvider"
         />
         <service id="Sylius\InvoicingPlugin\Provider\UnitNetPriceProviderInterface" alias="sylius_invoicing.provider.unit_net_price" />
+
+        <service id="sylius_invoicing.provider.item_net_prices" class="Sylius\InvoicingPlugin\Provider\ItemNetPricesProvider">
+            <argument type="service" id="sylius.distributor.integer" />
+        </service>
+        <service id="Sylius\InvoicingPlugin\Provider\ItemNetPricesProviderInterface" alias="sylius_invoicing.provider.item_net_prices" />
     </services>
 </container>
diff --git a/config/services/converters.xml b/config/services/converters.xml
index e28df52e..9fb60ab2 100644
--- a/config/services/converters.xml
+++ b/config/services/converters.xml
@@ -23,6 +23,12 @@
             <argument type="service" id="sylius_invoicing.provider.unit_net_price" />
         </service>
 
+        <service id="sylius_invoicing.converter.order_item_to_line_items" class="Sylius\InvoicingPlugin\Converter\OrderItemsToLineItemsConverter">
+            <argument type="service" id="sylius_invoicing.provider.tax_rate_percentage" />
+            <argument type="service" id="sylius_invoicing.factory.line_item" />
+            <argument type="service" id="sylius_invoicing.provider.item_net_prices" />
+        </service>
+
         <service id="sylius_invoicing.converter.shipping_adjustments_to_line_items" class="Sylius\InvoicingPlugin\Converter\ShippingAdjustmentsToLineItemsConverter">
             <argument type="service" id="sylius_invoicing.provider.tax_rate_percentage" />
             <argument type="service" id="sylius_invoicing.factory.line_item" />
diff --git a/config/services/generators.xml b/config/services/generators.xml
index cfca0642..533baa54 100644
--- a/config/services/generators.xml
+++ b/config/services/generators.xml
@@ -35,6 +35,7 @@
             <argument type="service" id="sylius_invoicing.converter.order_item_units_to_line_items" />
             <argument type="service" id="sylius_invoicing.converter.shipping_adjustments_to_line_items" />
             <argument type="service" id="sylius_invoicing.converter.tax_items" />
+            <argument type="service" id="sylius_invoicing.converter.order_item_to_line_items" />
         </service>
         <service id="Sylius\InvoicingPlugin\Generator\InvoiceGeneratorInterface" alias="sylius_invoicing.generator.invoice" />
 
diff --git a/features/managing_invoices/seeing_invoice_with_taxes_included_in_price_and_promotions_applied.feature b/features/managing_invoices/seeing_invoice_with_taxes_included_in_price_and_promotions_applied.feature
index 4662f1c9..6eb153ac 100644
--- a/features/managing_invoices/seeing_invoice_with_taxes_included_in_price_and_promotions_applied.feature
+++ b/features/managing_invoices/seeing_invoice_with_taxes_included_in_price_and_promotions_applied.feature
@@ -22,6 +22,6 @@ Feature: Seeing included in price taxes and promotions applied on an invoice
 
     Scenario: Seeing proper taxes and promotions on an invoice
         When I view the summary of the invoice for order "#00000666"
-        Then it should have 2 "PHP T-Shirt" items with unit net price "50.65", discounted unit net price "40.65", net value "81.30", tax total "18.70" and total "100.00" in "USD" currency
+        Then it should have 2 "PHP T-Shirt" items with unit net price "48.78", discounted unit net price "40.65", net value "81.30", tax total "18.70" and total "100.00" in "USD" currency
         And it should have a tax item "23%" with amount "18.70" in "USD" currency
         And its total should be "110.00" in "USD" currency
diff --git a/src/Converter/OrderItemsToLineItemsConverter.php b/src/Converter/OrderItemsToLineItemsConverter.php
new file mode 100644
index 00000000..e5e700f9
--- /dev/null
+++ b/src/Converter/OrderItemsToLineItemsConverter.php
@@ -0,0 +1,110 @@
+<?php
+
+/*
+ * This file is part of the Sylius package.
+ *
+ * (c) Sylius Sp. z o.o.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Sylius\InvoicingPlugin\Converter;
+
+use Sylius\Component\Core\Model\OrderInterface;
+use Sylius\Component\Core\Model\OrderItemInterface;
+use Sylius\Component\Core\Model\OrderItemUnitInterface;
+use Sylius\InvoicingPlugin\Entity\LineItemInterface;
+use Sylius\InvoicingPlugin\Factory\LineItemFactoryInterface;
+use Sylius\InvoicingPlugin\Provider\ItemNetPricesProviderInterface;
+use Sylius\InvoicingPlugin\Provider\TaxRatePercentageProviderInterface;
+use Webmozart\Assert\Assert;
+
+final class OrderItemsToLineItemsConverter implements LineItemsConverterInterface
+{
+    public function __construct(
+        private readonly TaxRatePercentageProviderInterface $taxRatePercentageProvider,
+        private readonly LineItemFactoryInterface $lineItemFactory,
+        private readonly ItemNetPricesProviderInterface $unitNetPriceProvider,
+    ) {
+    }
+
+    public function convert(OrderInterface $order): array
+    {
+        $lineItems = [];
+
+        /** @var OrderItemInterface $item */
+        foreach ($order->getItems() as $item) {
+            foreach ($this->convertOrderItemToLineItems($item) as $lineItem) {
+                $lineItems = $this->addLineItem($lineItem, $lineItems);
+            }
+        }
+
+        return $lineItems;
+    }
+
+    private function convertOrderItemToLineItems(OrderItemInterface $item): array
+    {
+        $lineItems = [];
+        $units = $item->getUnits()->getValues();
+        $unitNetPrices = $this->unitNetPriceProvider->getItemNetPrices($item);
+
+        /** @var OrderItemUnitInterface $unit */
+        foreach ($units as $index => $unit) {
+            $lineItems = $this->addLineItem($this->convertOrderItemUnitToLineItem($unit, (int) $unitNetPrices[$index]), $lineItems);
+        }
+
+        return $lineItems;
+    }
+
+    private function convertOrderItemUnitToLineItem(OrderItemUnitInterface $unit, int $unitNetPrice): LineItemInterface
+    {
+        /** @var OrderItemInterface $item */
+        $item = $unit->getOrderItem();
+
+        $grossValue = $unit->getTotal();
+        $taxAmount = $unit->getTaxTotal();
+        $discountedUnitNetPrice = $grossValue - $taxAmount;
+
+        /** @var string|null $productName */
+        $productName = $item->getProductName();
+        Assert::notNull($productName);
+
+        $variant = $item->getVariant();
+
+        return $this->lineItemFactory->createWithData(
+            $productName,
+            1,
+            $unitNetPrice,
+            $discountedUnitNetPrice,
+            $discountedUnitNetPrice,
+            $taxAmount,
+            $grossValue,
+            $item->getVariantName(),
+            $variant !== null ? $variant->getCode() : null,
+            $this->taxRatePercentageProvider->provideFromAdjustable($unit),
+        );
+    }
+
+    /**
+     * @param LineItemInterface[] $lineItems
+     *
+     * @return LineItemInterface[]
+     */
+    private function addLineItem(LineItemInterface $newLineItem, array $lineItems): array
+    {
+        foreach ($lineItems as $lineItem) {
+            if ($lineItem->compare($newLineItem)) {
+                $lineItem->merge($newLineItem);
+
+                return $lineItems;
+            }
+        }
+
+        $lineItems[] = $newLineItem;
+
+        return $lineItems;
+    }
+}
diff --git a/src/Generator/InvoiceGenerator.php b/src/Generator/InvoiceGenerator.php
index 8241ca4e..c425265a 100644
--- a/src/Generator/InvoiceGenerator.php
+++ b/src/Generator/InvoiceGenerator.php
@@ -36,7 +36,23 @@ public function __construct(
         private readonly LineItemsConverterInterface $orderItemUnitsToLineItemsConverter,
         private readonly LineItemsConverterInterface $shippingAdjustmentsToLineItemsConverter,
         private readonly TaxItemsConverterInterface $taxItemsConverter,
+        private readonly ?LineItemsConverterInterface $orderItemsToLineItemsConverter = null,
     ) {
+        if (null === $this->orderItemsToLineItemsConverter) {
+            trigger_deprecation(
+                'sylius/invoicing-plugin',
+                '2.0',
+                'Not passing a "%s" to "%s" is deprecated and will be required in Sylius Invoicing Plugin 3.0.',
+                LineItemsConverterInterface::class,
+                self::class,
+            );
+            trigger_deprecation(
+                'sylius/invoicing-plugin',
+                '2.0',
+                'Deprecated constructor argument "$orderItemUnitsToLineItemsConverter" passed to %s. Use "$orderItemsToLineItemsConverter" instead.',
+                self::class,
+            );
+        }
     }
 
     public function generateForOrder(OrderInterface $order, \DateTimeInterface $date): InvoiceInterface
@@ -50,6 +66,10 @@ public function generateForOrder(OrderInterface $order, \DateTimeInterface $date
         $paymentState = $order->getPaymentState() === OrderPaymentStates::STATE_PAID ?
             InvoiceInterface::PAYMENT_STATE_COMPLETED : InvoiceInterface::PAYMENT_STATE_PENDING;
 
+        $lineItemsFromOrder = $this->orderItemsToLineItemsConverter !== null
+            ? $this->orderItemsToLineItemsConverter->convert($order)
+            : $this->orderItemUnitsToLineItemsConverter->convert($order);
+
         return $this->invoiceFactory->createForData(
             $this->uuidInvoiceIdentifierGenerator->generate(),
             $this->sequentialInvoiceNumberGenerator->generate(),
@@ -60,7 +80,7 @@ public function generateForOrder(OrderInterface $order, \DateTimeInterface $date
             $order->getLocaleCode(),
             $order->getTotal(),
             new ArrayCollection(array_merge(
-                $this->orderItemUnitsToLineItemsConverter->convert($order),
+                $lineItemsFromOrder,
                 $this->shippingAdjustmentsToLineItemsConverter->convert($order),
             )),
             $this->taxItemsConverter->convert($order),
diff --git a/src/Provider/ItemNetPricesProvider.php b/src/Provider/ItemNetPricesProvider.php
new file mode 100644
index 00000000..52213ebf
--- /dev/null
+++ b/src/Provider/ItemNetPricesProvider.php
@@ -0,0 +1,67 @@
+<?php
+
+/*
+ * This file is part of the Sylius package.
+ *
+ * (c) Sylius Sp. z o.o.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Sylius\InvoicingPlugin\Provider;
+
+use Sylius\Component\Core\Distributor\IntegerDistributorInterface;
+use Sylius\Component\Core\Model\AdjustmentInterface;
+use Sylius\Component\Core\Model\OrderItemInterface;
+use Sylius\Component\Core\Model\OrderItemUnitInterface;
+
+final class ItemNetPricesProvider implements ItemNetPricesProviderInterface
+{
+    public function __construct(
+        private IntegerDistributorInterface $distributor,
+    ) {
+    }
+
+    public function getItemNetPrices(OrderItemInterface $orderItem): array
+    {
+        /** @var OrderItemUnitInterface|null $orderItemUnit */
+        $orderItemUnit = $orderItem->getUnits()->first();
+
+        if (null === $orderItemUnit) {
+            return [];
+        }
+
+        $taxRate = $this->getTaxRate($orderItemUnit);
+        $grossTotal = $orderItem->getQuantity() * $orderItem->getUnitPrice();
+
+        $itemNetPrice = ($grossTotal / (100 + ($taxRate))) * 100;
+
+        return array_reverse($this->distributor->distribute(round($itemNetPrice, 1), $orderItem->getQuantity()));
+    }
+
+    private function getTaxRate(OrderItemUnitInterface $orderItemUnit): int
+    {
+        $taxRate = 0;
+
+        /** @var AdjustmentInterface $adjustment */
+        foreach ($orderItemUnit->getAdjustments(AdjustmentInterface::TAX_ADJUSTMENT) as $adjustment) {
+            if (!$adjustment->isNeutral()) {
+                continue;
+            }
+
+            try {
+                $details = $adjustment->getDetails();
+                if (is_array($details) && array_key_exists('taxRateAmount', $details) && is_numeric($details['taxRateAmount'])) {
+                    $taxRate = $details['taxRateAmount'] * 100;
+                }
+            } catch (\Throwable $e) {
+                throw new \RuntimeException('Tax rate amount is not valid', 0, $e);
+            }
+        }
+
+        return (int) round($taxRate);
+    }
+}
diff --git a/src/Provider/ItemNetPricesProviderInterface.php b/src/Provider/ItemNetPricesProviderInterface.php
new file mode 100644
index 00000000..0f26e10c
--- /dev/null
+++ b/src/Provider/ItemNetPricesProviderInterface.php
@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of the Sylius package.
+ *
+ * (c) Sylius Sp. z o.o.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Sylius\InvoicingPlugin\Provider;
+
+use Sylius\Component\Core\Model\OrderItemInterface;
+
+interface ItemNetPricesProviderInterface
+{
+    public function getItemNetPrices(OrderItemInterface $orderItem): array;
+}
diff --git a/src/Provider/UnitNetPriceProvider.php b/src/Provider/UnitNetPriceProvider.php
index 4af6cf24..695bd641 100644
--- a/src/Provider/UnitNetPriceProvider.php
+++ b/src/Provider/UnitNetPriceProvider.php
@@ -16,6 +16,7 @@
 use Sylius\Component\Core\Model\AdjustmentInterface;
 use Sylius\Component\Core\Model\OrderItemUnitInterface;
 
+/** @deprecated since Sylius Invoicing Plugin 2.0 and will be removed in Sylius Invoicing Plugin 3.0. */
 final class UnitNetPriceProvider implements UnitNetPriceProviderInterface
 {
     public function getUnitNetPrice(OrderItemUnitInterface $orderItemUnit): int