diff --git a/BTCPayServer.Client/BTCPayServerClient.Invoices.cs b/BTCPayServer.Client/BTCPayServerClient.Invoices.cs
index a7518aafb..87f3215db 100644
--- a/BTCPayServer.Client/BTCPayServerClient.Invoices.cs
+++ b/BTCPayServer.Client/BTCPayServerClient.Invoices.cs
@@ -54,6 +54,17 @@ namespace BTCPayServer.Client
             return await HandleResponse<InvoiceData>(response);
         }
 
+        public virtual async Task<InvoiceData> UpdateInvoice(string storeId, string invoiceId,
+            UpdateInvoiceRequest request, CancellationToken token = default)
+        {
+            if (request == null)
+                throw new ArgumentNullException(nameof(request));
+            var response = await _httpClient.SendAsync(
+                CreateHttpRequest($"api/v1/stores/{storeId}/invoices/{invoiceId}", bodyPayload: request,
+                    method: HttpMethod.Put), token);
+            return await HandleResponse<InvoiceData>(response);
+        }
+
         public virtual async Task<InvoiceData> MarkInvoiceStatus(string storeId, string invoiceId,
             MarkInvoiceStatusRequest request, CancellationToken token = default)
         {
diff --git a/BTCPayServer.Client/Models/UpdateInvoiceRequest.cs b/BTCPayServer.Client/Models/UpdateInvoiceRequest.cs
new file mode 100644
index 000000000..af4586863
--- /dev/null
+++ b/BTCPayServer.Client/Models/UpdateInvoiceRequest.cs
@@ -0,0 +1,9 @@
+using Newtonsoft.Json.Linq;
+
+namespace BTCPayServer.Client.Models
+{
+    public class UpdateInvoiceRequest
+    {
+        public JObject Metadata { get; set; }
+    }
+}
diff --git a/BTCPayServer.Tests/GreenfieldAPITests.cs b/BTCPayServer.Tests/GreenfieldAPITests.cs
index ae2c15ceb..7b030056d 100644
--- a/BTCPayServer.Tests/GreenfieldAPITests.cs
+++ b/BTCPayServer.Tests/GreenfieldAPITests.cs
@@ -978,7 +978,22 @@ namespace BTCPayServer.Tests
                     });
                 });
 
+                await AssertHttpError(403, async () =>
+                {
+                    await viewOnly.UpdateInvoice(user.StoreId, newInvoice.Id,
+                        new UpdateInvoiceRequest()
+                        {
+                            Metadata = JObject.Parse("{\"itemCode\": \"updated\", newstuff: [1,2,3,4,5]}")
+                        });
+                });
+                invoice = await client.UpdateInvoice(user.StoreId, newInvoice.Id,
+                    new UpdateInvoiceRequest()
+                    {
+                        Metadata = JObject.Parse("{\"itemCode\": \"updated\", newstuff: [1,2,3,4,5]}")
+                    });
 
+                Assert.Equal("updated",invoice.Metadata["itemCode"].Value<string>());
+                Assert.Equal(15,((JArray) invoice.Metadata["newstuff"]).Values<int>().Sum());
                 //archive 
                 await AssertHttpError(403, async () =>
                 {
diff --git a/BTCPayServer/Controllers/GreenField/InvoiceController.cs b/BTCPayServer/Controllers/GreenField/InvoiceController.cs
index bcd303718..0b3235f17 100644
--- a/BTCPayServer/Controllers/GreenField/InvoiceController.cs
+++ b/BTCPayServer/Controllers/GreenField/InvoiceController.cs
@@ -4,21 +4,16 @@ using System.Threading.Tasks;
 using BTCPayServer.Abstractions.Constants;
 using BTCPayServer.Client;
 using BTCPayServer.Client.Models;
-using BTCPayServer.Models.InvoicingModels;
 using BTCPayServer.Payments;
 using BTCPayServer.Security;
 using BTCPayServer.Services;
 using BTCPayServer.Services.Invoices;
-using BTCPayServer.Validation;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Cors;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Routing;
 using Microsoft.EntityFrameworkCore.Metadata.Conventions;
 using NBitcoin;
-using NBitpayClient;
-using Newtonsoft.Json;
-using Newtonsoft.Json.Linq;
 using CreateInvoiceRequest = BTCPayServer.Client.Models.CreateInvoiceRequest;
 using InvoiceData = BTCPayServer.Client.Models.InvoiceData;
 
@@ -100,6 +95,26 @@ namespace BTCPayServer.Controllers.GreenField
             return Ok();
         }
 
+        [Authorize(Policy = Policies.CanModifyStoreSettings,
+            AuthenticationSchemes = AuthenticationSchemes.Greenfield)]
+        [HttpPut("~/api/v1/stores/{storeId}/invoices/{invoiceId}")]
+        public async Task<IActionResult> UpdateInvoice(string storeId, string invoiceId, UpdateInvoiceRequest request)
+        {
+            var store = HttpContext.GetStoreData();
+            if (store == null)
+            {
+                return NotFound();
+            }
+
+            var result = await _invoiceRepository.UpdateInvoiceMetadata(invoiceId, storeId, request.Metadata);
+            if (result != null)
+            {
+                return Ok(ToModel(result));
+            }
+
+            return NotFound();
+        }
+
         [Authorize(Policy = Policies.CanCreateInvoice,
             AuthenticationSchemes = AuthenticationSchemes.Greenfield)]
         [HttpPost("~/api/v1/stores/{storeId}/invoices")]
diff --git a/BTCPayServer/Services/Invoices/InvoiceRepository.cs b/BTCPayServer/Services/Invoices/InvoiceRepository.cs
index 4b6d83255..ca19f2fcf 100644
--- a/BTCPayServer/Services/Invoices/InvoiceRepository.cs
+++ b/BTCPayServer/Services/Invoices/InvoiceRepository.cs
@@ -441,6 +441,22 @@ retry:
                 await context.SaveChangesAsync().ConfigureAwait(false);
             }
         }
+        public async Task<InvoiceEntity> UpdateInvoiceMetadata(string invoiceId,  string storeId, JObject metadata)
+        {
+            using (var context = _ContextFactory.CreateContext())
+            {
+                var invoiceData = await GetInvoiceRaw(invoiceId);
+                if (invoiceData == null || (storeId != null &&
+                                            !invoiceData.StoreDataId.Equals(storeId,
+                                                StringComparison.InvariantCultureIgnoreCase)))
+                    return null;
+                var blob = invoiceData.GetBlob(_Networks);
+                blob.Metadata =  InvoiceMetadata.FromJObject(metadata);
+                invoiceData.Blob = ToBytes(blob);
+                await context.SaveChangesAsync().ConfigureAwait(false);
+                return ToEntity(invoiceData);
+            }
+        }
         public async Task<bool> MarkInvoiceStatus(string invoiceId, InvoiceStatus status)
         {
             using (var context = _ContextFactory.CreateContext())
diff --git a/BTCPayServer/wwwroot/swagger/v1/swagger.template.invoices.json b/BTCPayServer/wwwroot/swagger/v1/swagger.template.invoices.json
index ccc133cf8..ade84ea05 100644
--- a/BTCPayServer/wwwroot/swagger/v1/swagger.template.invoices.json
+++ b/BTCPayServer/wwwroot/swagger/v1/swagger.template.invoices.json
@@ -214,6 +214,80 @@
                         "Basic": []
                     }
                 ]
+            },
+            "put": {
+                "tags": [
+                    "Invoices"
+                ],
+                "summary": "Update invoice",
+                "description": "Updates the specified invoice.",
+                "operationId": "Invoices_UpdateInvoice",
+                "parameters": [
+                    {
+                        "name": "storeId",
+                        "in": "path",
+                        "required": true,
+                        "description": "The store the invoice belongs to",
+                        "schema": {
+                            "type": "string"
+                        }
+                    },
+                    {
+                        "name": "invoiceId",
+                        "in": "path",
+                        "required": true,
+                        "description": "The invoice to update",
+                        "schema": {
+                            "type": "string"
+                        }
+                    }
+                ],
+                "responses": {
+                    "200": {
+                        "description": "The invoice that has been updated",
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "$ref": "#/components/schemas/InvoiceData"
+                                }
+                            }
+                        }
+                    },
+                    "400": {
+                        "description": "A list of errors that occurred when updating the invoice",
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "$ref": "#/components/schemas/ValidationProblemDetails"
+                                }
+                            }
+                        }
+                    },
+                    "403": {
+                        "description": "If you are authenticated but forbidden to update the specified invoice"
+                    },
+                    "404": {
+                        "description": "The key is not found for this invoice"
+                    }
+                },
+                "requestBody": {
+                    "required": true,
+                    "content": {
+                        "application/json": {
+                            "schema": {
+                                "$ref": "#/components/schemas/UpdateInvoiceRequest"
+                            }
+                        }
+                    }
+                },
+                "security": [
+                    {
+                        "API Key": [
+                            "btcpay.store.canmodifystoresettings"
+                        ],
+                        "Basic": []
+                    }
+                ]
             }
         },
         "/api/v1/stores/{storeId}/invoices/{invoiceId}/payment-methods": {
@@ -628,6 +702,17 @@
                     }
                 }
             },
+            "UpdateInvoiceRequest": {
+                "type": "object",
+                "additionalProperties": false,
+                "properties": {
+                    "metadata": {
+                        "type": "object",
+                        "nullable": true,
+                        "description": "Additional information around the invoice that can be supplied."
+                    }
+                }
+            },
             "CheckoutOptions": {
                 "type": "object",
                 "additionalProperties": false,