diff --git a/CHANGELOG.md b/CHANGELOG.md
index d24839a..5bcff17 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## Unreleased
 
 - Support for PHP 8.3
+- Handle file uploads and invoice, expense attachments
 - Handle new API version webhook event errors
 
 ## 0.7.0
diff --git a/README.md b/README.md
index 23178bc..f9306e2 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 [![Packagist Version](https://badgen.net/packagist/v/amcintosh/freshbooks)](https://packagist.org/packages/amcintosh/freshbooks)
 ![Packagist PHP Version Support](https://img.shields.io/packagist/php-v/amcintosh/freshbooks)
-[![GitHub Workflow Status](https://img.shields.io/github/workflow/status/amcintosh/freshbooks-php-sdk/Run%20Tests)](https://github.com/amcintosh/freshbooks-php-sdk/actions?query=workflow%3A%22Run+Tests%22)
+[![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/amcintosh/freshbooks-php-sdk/run-tests.yml?branch=main)](https://github.com/amcintosh/freshbooks-php-sdk/actions?query=workflow%3A%22Run+Tests%22)
 
 A FreshBooks PHP SDK to allow you to more easily utilize the [FreshBooks API](https://www.freshbooks.com/api).
 This library is not directly maintained by FreshBooks and [community contributions](CONTRIBUTING.md) are welcome.
diff --git a/composer.json b/composer.json
index 3ea46de..ed7805c 100644
--- a/composer.json
+++ b/composer.json
@@ -6,6 +6,7 @@
         "php": ">=8.0 <8.4",
         "php-http/client-common": "^2.5",
         "php-http/discovery": "^1.14",
+        "php-http/multipart-stream-builder": "^1.3",
         "psr/http-client": "^1.0",
         "psr/http-factory": "^1.0",
         "spatie/data-transfer-object": "^3.8",
diff --git a/docs/source/api-calls/errors.rst b/docs/source/api-calls/errors.rst
index a0ca9e0..38aa1d5 100644
--- a/docs/source/api-calls/errors.rst
+++ b/docs/source/api-calls/errors.rst
@@ -17,8 +17,8 @@ Example:
         echo $e->getCode();        // 404
         echo $e->getErrorCode();   // 1012
         echo $e->getRawResponse(); // '{"response": {"errors": [{"errno": 1012,
-                                // "field": "userid", "message": "Client not found.",
-                                // "object": "client", "value": "134"}]}}'
+                                   // "field": "userid", "message": "Client not found.",
+                                   // "object": "client", "value": "134"}]}}'
     }
 
 Not all resources have full CRUD methods available. For example expense categories have ``list`` and ``get``
diff --git a/docs/source/file-uploads.rst b/docs/source/file-uploads.rst
new file mode 100644
index 0000000..bc16b6d
--- /dev/null
+++ b/docs/source/file-uploads.rst
@@ -0,0 +1,73 @@
+File Uploads
+============
+
+Some FreshBooks resource can include images and attachments. For example, invoices can have a company
+logo or banner image as part of the invoice presentation object as well as images or pdfs attachments.
+Expenses can also include copies or photos of receipts as attachments.
+
+All images and attachments first need to be uploaded to FreshBooks via the ``images`` or ``attachments``
+endpoints.
+
+These will then return a path to your file with a JWT. This path will can then be passed as part of the
+data in a subsequent call.
+
+See FreshBooks' `invoice attachment <https://www.freshbooks.com/api/invoice_presentation_attachments>`_
+and `expense attachment <https://www.freshbooks.com/api/https://www.freshbooks.com/api/expense-attachments>`_
+documentation for more information.
+
+Invoice Images and Attachments
+------------------------------
+
+See `FreshBooks' API Documentation <https://www.freshbooks.com/api/invoice_presentation_attachments>`_.
+
+The ``upload()`` function takes a `PHP resource <https://www.php.net/manual/en/language.types.resource.php>`_.
+Logo's and banners are added to the invoice presentation object. To include an uploaded attachment on
+an invoice, the invoice request must include an attachments object.
+
+.. code-block:: php
+    $logo = $freshBooksClient->images()->upload($accountId, fopen('./sample_logo.png', 'r'));
+    $attachment = $freshBooksClient->attachments()->upload($accountId, fopen('./sample_attachment.pdf', 'r'));
+
+    $presentation = [
+        'image_logo_src' => "/uploads/images/{$logo->jwt}",
+        'theme_primary_color' => '#1fab13',
+        'theme_layout' => 'simple'
+    ];
+
+    $invoiceData = [
+        'customerid' => $clientId,
+        'attachments' => [
+            [
+                'jwt' => $attachment->jwt,
+                'media_type' => $attachment->mediaType
+            ]
+        ],
+        'presentation' => presentation
+    ];
+
+    $invoice = $freshBooksClient->invoices()->create($accountId, $invoiceData);
+
+Expense Receipts
+----------------
+
+See `FreshBooks' API Documentation <https://www.freshbooks.com/api/expense-attachments>`_.
+
+Expenses have have images or PDFs of the associated receipt attached. The expense request must include
+an attachments object.
+
+.. code-block:: php
+    $attachment = $freshBooksClient->attachments()->upload($accountId, fopen('./sample_receipt.pdf', 'r'));
+
+    $expense->amount = new Money("6.49", "CAD");
+    $expense->date = new DateTime();
+    $expense->staffId = 1;
+    $expense->categoryId = 3436009;
+
+    $expenseAttachment = new ExpenseAttachment();
+    $expenseAttachment->jwt = $attachment->jwt;
+    $expenseAttachment->mediaType = $attachment->mediaType;
+
+    $expense->attachment = $expenseAttachment;
+
+    $includes = (new IncludesBuilder())->include('attachment');
+    $expense = $freshBooksClient->expenses()->create($accountId, model: $expense, includes: $includes);
diff --git a/docs/source/index.rst b/docs/source/index.rst
index 4678095..429920d 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -9,6 +9,7 @@
    configuration
    authorization
    api-calls/index
+   file-uploads
    webhooks
    examples
 
diff --git a/src/FreshBooksClient.php b/src/FreshBooksClient.php
index bf1ebbe..5301af0 100644
--- a/src/FreshBooksClient.php
+++ b/src/FreshBooksClient.php
@@ -43,6 +43,7 @@
 use amcintosh\FreshBooks\Resource\EventsResource;
 use amcintosh\FreshBooks\Resource\PaymentResource;
 use amcintosh\FreshBooks\Resource\ProjectResource;
+use amcintosh\FreshBooks\Resource\UploadResource;
 
 /**
  * SDK Client.
@@ -349,4 +350,24 @@ public function invoicePaymentOptions(): PaymentResource
             staticPathParams: 'entity_type=invoice',
         );
     }
+
+    /**
+     * FreshBooks attachment upload resource with call to upload, get
+     *
+     * @return UploadResource
+     */
+    public function attachments(): UploadResource
+    {
+        return new UploadResource($this->httpClient, 'attachments', 'attachment');
+    }
+
+    /**
+     * FreshBooks image upload resource with call to upload, get
+     *
+     * @return UploadResource
+     */
+    public function images(): UploadResource
+    {
+        return new UploadResource($this->httpClient, 'images', 'image');
+    }
 }
diff --git a/src/Model/ExpenseAttachment.php b/src/Model/ExpenseAttachment.php
index ac47ba8..1e1f762 100644
--- a/src/Model/ExpenseAttachment.php
+++ b/src/Model/ExpenseAttachment.php
@@ -4,16 +4,11 @@
 
 namespace amcintosh\FreshBooks\Model;
 
-use DateTime;
-use DateTimeImmutable;
-use Spatie\DataTransferObject\Attributes\CastWith;
 use Spatie\DataTransferObject\Attributes\MapFrom;
 use Spatie\DataTransferObject\Attributes\MapTo;
 use Spatie\DataTransferObject\Caster;
 use Spatie\DataTransferObject\DataTransferObject;
 use amcintosh\FreshBooks\Model\DataModel;
-use amcintosh\FreshBooks\Model\Caster\AccountingDateTimeImmutableCaster;
-use amcintosh\FreshBooks\Model\Caster\MoneyCaster;
 
 /**
  * Attached receipt image details for an expense.
@@ -22,7 +17,7 @@
  * present with the use of a corresponding "includes" filter.
  *
  * @package amcintosh\FreshBooks\Model
- * @link https://www.freshbooks.com/api/expenses
+ * @link https://www.freshbooks.com/api/expense-attachments
  */
 class ExpenseAttachment extends DataTransferObject implements DataModel
 {
diff --git a/src/Model/FileUpload.php b/src/Model/FileUpload.php
new file mode 100644
index 0000000..ca1a145
--- /dev/null
+++ b/src/Model/FileUpload.php
@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace amcintosh\FreshBooks\Model;
+
+use Psr\Http\Message\StreamInterface;
+
+/**
+ * A file that has been uploaded to FreshBooks.
+ *
+ * @package amcintosh\FreshBooks\Model
+ */
+class FileUpload
+{
+    /**
+     * @var string The JWT used to fetch the file from FreshBooks.
+     */
+    public ?string $jwt;
+
+    /**
+     * @var string The name of the file uploaded to FreshBooks.
+     *
+     * This is returned from the API in the `X-filename` header.
+     */
+    public ?string $fileName;
+
+    /**
+     * @var string The media type (eg. `image/png`) of the file uploaded to FreshBooks.
+     */
+    public ?string $mediaType;
+
+    /**
+     * @var string The PSR StreamInterface steam of data from the request body.
+     */
+    public ?StreamInterface $responseBody;
+
+    /**
+     * @var string A fully qualified path the the file from FreshBooks.
+     */
+    public ?string $link;
+
+    public function __construct(?string $fileName, ?string $mediaType, ?StreamInterface $responseBody)
+    {
+        $this->fileName = $fileName;
+        $this->mediaType = $mediaType;
+        $this->responseBody = $responseBody;
+    }
+}
diff --git a/src/Model/InvoiceAttachment.php b/src/Model/InvoiceAttachment.php
new file mode 100644
index 0000000..b56b335
--- /dev/null
+++ b/src/Model/InvoiceAttachment.php
@@ -0,0 +1,74 @@
+<?php
+
+declare(strict_types=1);
+
+namespace amcintosh\FreshBooks\Model;
+
+use Spatie\DataTransferObject\Attributes\MapFrom;
+use Spatie\DataTransferObject\Attributes\MapTo;
+use Spatie\DataTransferObject\Caster;
+use Spatie\DataTransferObject\DataTransferObject;
+use amcintosh\FreshBooks\Model\DataModel;
+
+/**
+ * Attached files and images to include with an invoice.
+ *
+ * _Note:_ This data is not in the default response and will only be
+ * present with the use of a corresponding "includes" filter.
+ *
+ * @package amcintosh\FreshBooks\Model
+ * @link https://www.freshbooks.com/api/invoice_presentation_attachments
+ */
+class InvoiceAttachment extends DataTransferObject implements DataModel
+{
+    public const RESPONSE_FIELD = 'expense';
+
+    /**
+     * @var int The unique identifier of this expense attachment within this business.
+     */
+    public ?int $id;
+
+    /**
+     * @var int Duplicate of id
+     */
+    #[MapFrom('attachmentid')]
+    public ?int $attachmentId;
+
+    /**
+     * @var int Id of the expense this attachment is associated with, if applicable.
+     */
+    #[MapFrom('expenseid')]
+    #[MapTo('expenseid')]
+    public ?int $expenseId;
+
+    /**
+     * @var string JWT link to the attachment.
+     */
+    public ?string $jwt;
+
+    /**
+     * @var string Type of the attachment.
+     */
+    #[MapFrom('media_type')]
+    #[MapTo('media_type')]
+    public ?string $mediaType;
+
+    /**
+     * Get the data as an array to POST or PUT to FreshBooks, removing any read-only fields.
+     *
+     * @return array
+     */
+    public function getContent(): array
+    {
+        $data = $this
+            ->except('id')
+            ->except('attachmentId')
+            ->toArray();
+        foreach ($data as $key => $value) {
+            if (is_null($value)) {
+                unset($data[$key]);
+            }
+        }
+        return $data;
+    }
+}
diff --git a/src/Resource/UploadResource.php b/src/Resource/UploadResource.php
new file mode 100644
index 0000000..35bf898
--- /dev/null
+++ b/src/Resource/UploadResource.php
@@ -0,0 +1,159 @@
+<?php
+
+declare(strict_types=1);
+
+namespace amcintosh\FreshBooks\Resource;
+
+use Http\Client\HttpClient;
+use Http\Discovery\HttpClientDiscovery;
+use Http\Discovery\Psr17FactoryDiscovery;
+use Http\Message\MultipartStream\MultipartStreamBuilder;
+use amcintosh\FreshBooks\Exception\FreshBooksException;
+use amcintosh\FreshBooks\Model\FileUpload;
+
+class UploadResource extends BaseResource
+{
+    protected HttpClient $httpClient;
+    protected string $uploadPath;
+    protected string $resourceName;
+
+    public function __construct(
+        HttpClient $httpClient,
+        string $uploadPath,
+        string $resourceName,
+    ) {
+        $this->httpClient = $httpClient;
+        $this->uploadPath = $uploadPath;
+        $this->resourceName = $resourceName;
+    }
+
+    /**
+     * The the url to the upload resource.
+     *
+     * @param  string $accountId
+     * @param  int $resourceId
+     * @return string
+     */
+    protected function getUrl(string $accountId = null, string $jwt = null): string
+    {
+        if (!is_null($accountId)) {
+            return "/uploads/account/{$accountId}/{$this->uploadPath}";
+        }
+        return "/uploads/{$this->uploadPath}/{$jwt}";
+    }
+
+    /**
+     * Create a FreshBooksException from the json response from the uploads endpoint.
+     *
+     * @param  int $statusCode HTTP status code
+     * @param  string $contents The response contents
+     * @return void
+     */
+    protected function handleError(int $statusCode, string $contents): void
+    {
+        try {
+            $responseData = json_decode($contents, true);
+        } catch (JSONDecodeError $e) {
+            throw new FreshBooksException('Failed to parse response', $statusCode, $e, $contents);
+        }
+        $message = $responseData['error'] ?? "Unknown error";
+        throw new FreshBooksException($message, $statusCode, null, $contents, null, null);
+    }
+
+    /**
+     * Make a request against the uploads resource. Returns an object containing a
+     * Psr\Http\Message\StreamInterface for flexibility.
+     * Throws a FreshBooksException if the response is not a 200.
+     *
+     * @param  string $url
+     * @return FileUpload
+     */
+    private function makeGetFileRequest(string $url): FileUpload
+    {
+        $response = $this->httpClient->send(self::GET, $url);
+        $responseBody = $response->getBody();
+        $statusCode = $response->getStatusCode();
+        if ($statusCode >= 400) {
+            $this->handleError($statusCode, $responseBody->getContents());
+        }
+        $fileName = $response->getHeader('X-filename');
+        if (!is_null($fileName) && count($fileName) > 0) {
+            $fileName = $fileName[0];
+        }
+        $mediaType = $response->getHeader('Content-Type');
+        if (!is_null($mediaType) && count($mediaType) > 0) {
+            $mediaType = $mediaType[0];
+        }
+
+        return new FileUpload($fileName, $mediaType, $responseBody);
+    }
+
+    /**
+     * Make creates a POST request to upload a file to FreshBooks.
+     * Throws a FreshBooksException if the response is not a 200.
+     *
+     * @param  string $url
+     * @return FileUpload
+     */
+    private function makeUploadRequest(string $url, $file): FileUpload
+    {
+        // Thank you https://dev.to/timoschinkel/sending-multipart-data-with-psr-18-2lb5
+        $streamFactory = Psr17FactoryDiscovery::findStreamFactory();
+
+        $builder = new MultipartStreamBuilder($streamFactory);
+        $builder->addResource('content', $file);
+
+        $requestFactory = Psr17FactoryDiscovery::findRequestFactory();
+        $request = $requestFactory
+            ->createRequest('POST', $url)
+            ->withHeader('Content-Type', 'multipart/form-data; boundary="' . $builder->getBoundary() . '"')
+            ->withBody($builder->build());
+
+        $response = $this->httpClient->sendRequest($request);
+
+        $statusCode = $response->getStatusCode();
+        $responseBody = $response->getBody();
+        if ($statusCode >= 400) {
+            $this->handleError($statusCode, $responseBody->getContents());
+        }
+        try {
+            $contents = $responseBody->getContents();
+            $responseData = json_decode($contents, true);
+        } catch (JSONDecodeError $e) {
+            throw new FreshBooksException('Failed to parse response', $statusCode, $e, $contents);
+        }
+        if (is_null($responseData) || !array_key_exists($this->resourceName, $responseData)) {
+            throw new FreshBooksException('Returned an unexpected response', $statusCode, null, $contents);
+        }
+        $link = $responseData['link'] ?? null;
+        $responseData = $responseData[$this->resourceName];
+        $fileData = new FileUpload($responseData['filename'], $responseData['media_type'], null);
+        $fileData->link = $link;
+        $fileData->jwt = $responseData['jwt'];
+        return $fileData;
+    }
+
+    /**
+     * Get an uploaded file.
+     *
+     * @param  string $jwt JWT provided by FreshBooks when the file was uploaded.
+     * @return FileUpload Object containing the file name, content type, and stream of data.
+     */
+    public function get(string $jwt): FileUpload
+    {
+        return $this->makeGetFileRequest($this->getUrl(jwt: $jwt));
+    }
+
+    /**
+     * Upload a file to FreshBooks.
+     *
+     * @param  string $accountId The alpha-numeric account id
+     * @param  resource File resource to upload
+     * @return FileUpload Object containing the JWT, file name, content type.
+     */
+    public function upload(string $accountId, $file): FileUpload
+    {
+        $url = $this->getUrl($accountId);
+        return  $this->makeUploadRequest($url, $file);
+    }
+}
diff --git a/tests/Resource/BaseResourceTest.php b/tests/Resource/BaseResourceTest.php
index 9ba30b3..d093641 100644
--- a/tests/Resource/BaseResourceTest.php
+++ b/tests/Resource/BaseResourceTest.php
@@ -23,4 +23,28 @@ public function getMockHttpClient(int $status = 200, array $content = null): Moc
         $mockHttpClient->addResponse($response);
         return $mockHttpClient;
     }
+
+    public function getMockFileHttpClient(
+        int $status = 200,
+        $file = null,
+        $fileName = null,
+        $contentType = null
+    ): MockHttpClient {
+        $mockHttpClient = new MockHttpClient(
+            Psr17FactoryDiscovery::findRequestFactory(),
+            Psr17FactoryDiscovery::findStreamFactory()
+        );
+        $fileHandle = fopen($file, 'r');
+        $headers = [
+            ['X-filename', [$fileName]],
+            ['Content-Type', [$contentType]]
+        ];
+
+        $response = $this->createMock('Psr\Http\Message\ResponseInterface');
+        $response->method('getStatusCode')->will($this->returnValue($status));
+        $response->method('getBody')->will($this->returnValue(Psr7\Utils::streamFor($fileHandle)));
+        $response->method('getHeader')->will($this->returnValueMap($headers));
+        $mockHttpClient->addResponse($response);
+        return $mockHttpClient;
+    }
 }
diff --git a/tests/Resource/UploadResourceTest.php b/tests/Resource/UploadResourceTest.php
new file mode 100644
index 0000000..f99b2ff
--- /dev/null
+++ b/tests/Resource/UploadResourceTest.php
@@ -0,0 +1,144 @@
+<?php
+
+declare(strict_types=1);
+
+namespace amcintosh\FreshBooks\Tests\Resource;
+
+use PHPUnit\Framework\TestCase;
+use amcintosh\FreshBooks\Exception\FreshBooksException;
+use amcintosh\FreshBooks\Resource\UploadResource;
+use amcintosh\FreshBooks\Tests\Resource\BaseResourceTest;
+
+final class UploadResourceTest extends TestCase
+{
+    use BaseResourceTest;
+
+    public string $accountId;
+
+    protected function setUp(): void
+    {
+        $this->accountId = 'ACM123';
+    }
+
+
+    public function testGet(): void
+    {
+        $fileName = 'sample_logo.png';
+        $contentType = 'image/png';
+        $mockHttpClient = $this->getMockFileHttpClient(
+            200,
+            'tests/Util/sample_logo.png',
+            $fileName,
+            $contentType
+        );
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+        $image = $resource->get($this->accountId, 'SOME_JWT');
+
+        $this->assertSame($fileName, $image->fileName);
+        $this->assertSame($contentType, $image->mediaType);
+        $request = $mockHttpClient->getLastRequest();
+        $this->assertSame('GET', $request->getMethod());
+        $this->assertSame('/uploads/images/ACM123', $request->getRequestTarget());
+    }
+
+    public function testGetWrongErrorContent(): void
+    {
+        $mockHttpClient = $this->getMockHttpClient(400, ['foo' => 'bar']);
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $this->expectException(FreshBooksException::class);
+        $this->expectExceptionMessage('Unknown error');
+
+        $resource->get('ACM123');
+    }
+
+    public function testGetNotFound(): void
+    {
+        $mockHttpClient = $this->getMockHttpClient(
+            404,
+            ['error' => 'File not found']
+        );
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $this->expectException(FreshBooksException::class);
+        $this->expectExceptionMessage('File not found');
+
+        $resource->get('ACM123');
+    }
+
+    public function testGetUnknownError(): void
+    {
+        $mockHttpClient = $this->getMockHttpClient(500);
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $this->expectException(FreshBooksException::class);
+        $this->expectExceptionMessage('Unknown error');
+
+        $resource->get('ACM123');
+    }
+
+
+    public function testUpload(): void
+    {
+        $jwt = 'some_jwt';
+        $fileName = 'upload-x123';
+        $contentType = 'image/png';
+        $mockHttpClient = $this->getMockHttpClient(
+            200,
+            [
+                'image' => [
+                    'filename' => $fileName,
+                    'public_id' => $jwt,
+                    'jwt' => $jwt,
+                    'media_type' => $contentType,
+                    'uuid' => 'some_uuid'
+                ],
+                'link' => "https://my.freshbooks.com/service/uploads/images/{$jwt}"
+            ]
+        );
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $imageData = $resource->upload($this->accountId, fopen('tests/Util/sample_logo.png', 'r'));
+
+        $this->assertSame($fileName, $imageData->fileName);
+        $this->assertSame($contentType, $imageData->mediaType);
+        $this->assertSame($jwt, $imageData->jwt);
+        $this->assertSame('https://my.freshbooks.com/service/uploads/images/some_jwt', $imageData->link);
+
+        $request = $mockHttpClient->getLastRequest();
+        $this->assertSame('POST', $request->getMethod());
+        $this->assertSame('/uploads/account/ACM123/images', $request->getRequestTarget());
+    }
+
+    public function testUploadBadRequest(): void
+    {
+        $mockHttpClient = $this->getMockHttpClient(
+            400,
+            ['error' => 'Content required']
+        );
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $this->expectException(FreshBooksException::class);
+        $this->expectExceptionMessage('Content required');
+
+        $imageData = $resource->upload($this->accountId, fopen('tests/Util/sample_logo.png', 'r'));
+    }
+
+    public function testUploadUnknownError(): void
+    {
+        $mockHttpClient = $this->getMockHttpClient(500);
+
+        $resource = new UploadResource($mockHttpClient, 'images', 'image');
+
+        $this->expectException(FreshBooksException::class);
+        $this->expectExceptionMessage('Unknown error');
+
+        $imageData = $resource->upload($this->accountId, fopen('tests/Util/sample_logo.png', 'r'));
+    }
+}
diff --git a/tests/Util/sample_logo.png b/tests/Util/sample_logo.png
new file mode 100644
index 0000000..e9eede5
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