MoMo API Sand Box Q&A

The Sandbox Collection token/payment flow and Sandbox User Provisioning endpoint are returning HTTP 500 Internal Server Error.I tested both the Primary and Secondary Collection subscription keys, but received the same result.Endpoint:POST https://sandbox.momodeveloper.mtn.com/v1_0/apiuserActivity IDs:e8bd5c96-1955-4c73-9b47-285372a833f0c7d94c70-d94b-419f-81f3-1b3f9606a18e903d8124-fc15-4129-9c88-a47d8c410224Please confirm whether the sandbox services are currently operational and advise when they will be restored.

Hitting 500, while trying to create api user key ??Please help us know,if its sandbox provisioning down or other thing else, or if the server is intentionally down mean like under maintenance !

Hello MTN MoMo team,I'm reporting a sandbox issue that started around 7 July 2026 and that I've been unable to resolve through the usual troubleshooting. I'd be grateful for your guidance on the likely cause and the recommended next step.SummaryMy Collections product subscription shows Active in the portal, and its subscription keys are accepted by the API gateway — but every request that is passed through to the backend hangs and never returns, timing out after roughly 30 seconds. This affects token generation and API-user management alike, so I cannot obtain an access token or provision a new API user.Behaviour observed (reproduced independently from two different networks using raw HTTP, so it is not specific to my application or hosting):Request Result POST /collection/token/ — valid Collections key + existing API user Times out (~37s), no response GET /v1_0/apiuser/{referenceId} — existing API user Times out (~21s), no response POST /v1_0/apiuser — create a new API user

I am trying to generate an api user and key for the sandbox environment.I am sure i am using the correct subscription key, and uuid.I tried the postman collection online. This returns the error: access_token or its expiry date are missing.Authentication is set to none, and i could not get this working.I then tried to create this request in a local postman install.The request looks the same as the online version, but returns error 404.The response body isContent-Length: 0Strict-Transport-Security: max-age=31536000; includeSubDomainsX-XSS-Protection: 1; mode=blockRequest-Context: appId=cid-v1:e996501c-e721-4ac1-97ff-dc6887b85e8cDate: Thu, 14 May 2026 10:02:01 GMT I have these headers: Ocp-Apim-Subscription-Key, X-Reference-Id, Content-Type. The request body is : {"providerCallbackHost":"www.google.com"}Any suggestion to resolve this will be highly appreciated. 

What is the difference between a RequestToPay and a RequestToWithdraw

Hi @all,I configured a user and api key. The call works (requesttopay), but the callback is not executed.I added the host dev.domain.com.xyHeader param for callback is “http://dev.domain.com.xy/webhook/mtnmomo”.No callback.Creating another user with callback domain “domain.com” it works…Any issues with “uncommon” domainnames? 

I’m getting invalid subscription key invalid while testing it in sandbox mode while testing it with live url it give resource not found.Below is for sandbox Mode.URL :: https://sandbox.momodeveloper.mtn.com/v1_0/apiuser headers :: {Authorization: Basic ZmY5NTZkMGYtODYwOC00NmZhLWIzMzEtZjRkNDhmNzAwZTNiOm51bGw=, X-Reference-Id: ff956d0f-8608-46fa-b331-f4d48f700e3b, Ocp-Apim-Subscription-Key: 84dbf7a8a0e44923988a0dd621169ec6, Content-Type: application/json} MtnMomo :: body :: {providerCallbackHost: https://dulu.cm/success} [log]MtnMomo :: apiuserAPI :: 401 :: { "statusCode": 401, "message": "Access denied due to invalid subscription key. Make sure to provide a valid key for an active subscription." }Below is for live testing URL :: https://proxy.momoapi.mtn.com/v1_0/apiuser headers :: {X-Reference-Id: 6e1fcdda-0cb1-4a85-8af6-8e3e6ff31942, Ocp-Apim-Subscription-Key: 0144c9f7b7774f4b8108cc4b243561b6, Content-Type: application/json}body :: {providerCallbackHost: https://dulu.cm/success}apiuse

I am building a platform that helps multiple businesses accept mobile money payments and automatically reconcile successful payments inside the system.I would like guidance on the best and officially supported setup for this model.My main concern is around how collections should work when one platform serves many merchant clients. If the integration is created under the platform account, does that mean funds are received into the platform’s collections account first, or can each client business receive its funds directly?We would prefer a setup where the platform does not have to hold or manage client funds if possible.I would also like to understand:whether each merchant needs its own setup or credentials whether there is any supported third-party, platform, or aggregator model whether it is possible to collect funds and immediately forward them to the merchant automatically whether extra charges apply in that kind of flow what the recommended approach is for this type of use caseAny

The request body below returns invalid currency. What currency codes work for Uganda? Tried altering the currencies but same error.{ "amount": "40000", "currency": "UGX", "externalId": "c1f4687688585858a173f12", "payer": { "partyIdType": "MSISDN", "partyId": "25678119xxxx" }, "payerMessage": "Payment for services", "payeeNote": "Payment for services"}

Hello MTN Developer Support,I have just started using the MTN Developer Portal and I am currently a student. I do not yet have a taxpayer number (NIU) or the business documents that are normally required for registration.I would like to know if there is a way for students or individuals without a taxpayer number to gain access to MTN APIs for learning, testing, or development purposes.Thank you for your guidance. 

We are no longer able to generate disbursement token since last few days. It was working before.The URL -  https://sandbox.momodeveloper.mtn.com/disbursement/token/Response Received:<html><head><title>Request Rejected</title></head><body>The requested URL was rejected. Please consult with your administrator.<br><br>Your support ID is: 14332579245721589193<br><br><a href='javascript:history.back();'>[Go Back]</a></body></html> 

Hi, getting the 500 internal server error without any details when trying to create API user as described here:https://momodeveloper.mtn.com/api-documentation/api-descriptionThe same result is with “Try it” feature on the site (https://momodeveloper.mtn.com/API-collections#api=sandbox-provisioning-api&operation=post-v1_0-apiuser&definition=ApiUser) and when calling it from the VPS. HTTP/1.1 500 Internal Server Errorcontent-length: 111content-type: application/jsonvary: Origin{ "statusCode": 500, "message": "Internal server error", "activityId": "93a3063e-****"}The system returns Activity ID where can I find details related to it?

Hi everyone,I’m having some trouble with the MTN MoMo API, specifically with the requestToPay endpoint.When I send a requestToPay, I get an HTTP 200 response, but the body looks like this: HTTP/1.1 200 OK cache-control: no-cache content-length: 247 content-type: text/html; charset=utf-8 pragma: no-cache vary: Origin x-content-type-options: nosniff x-frame-options: SAMEORIGIN x-xss-protection: 1; mode=block <html> <head><title>Request Rejected</title></head> <body> The requested URL was rejected. Please consult with your administrator.<br><br> Your support ID is: 11597720049318046811<br><br> <a href='javascript:history.back();'>[Go Back]</a> </body> </html> The problem is that no callback is ever sent, even though I receive this 200 response.Has anyone experienced this before or knows what might be wrong? Any help would be appreciated. 🙏 

Please assist, I am getting this error from the andbox  

Why I’m I getting this error when I try to create an API user for the sandbox environment?I could use some help

Where can I find the JavaScript implementation code for the Collection Widget? I need the widget.js URL and initialization code.

I have a WordPress site and I want to add an MTN collection widget to allow people to donate to our website using it?

HiI wanted to integrate payment gateway in my web application based on flutter web and node js, Can you pleas guide me step by step process for doing this. Also let me know about the required API keys and from where i can get these.Thanks

I believe I an following the instructions correctly. POST https://sandbox.momodeveloper.mtn.com/v1_0/apiuser HTTP/1.1X-Reference-Id: f9b22c29-eaeb-4423-9a29-960ece987648Content-Type: application/jsonCache-Control: no-cacheOcp-Apim-Subscription-Key: ••••••••••••••••••••••••••••••••{ providerCallbackHost: "string"}The X-Reference-Id is a UUID from online generator.Ocp-Apim-Subscription-Key is from mu Collection product.The result:HTTP/1.1 200 OKcache-control: no-cachecontent-length: 247content-type: text/html; charset=utf-8pragma: no-cachevary: Originx-content-type-options: nosniffx-frame-options: SAMEORIGINx-xss-protection: 1; mode=block<html><head><title>Request Rejected</title></head><body>The requested URL was rejected. Please consult with your administrator.<br><br>Your support ID is: 11597720049319855937<br><br><a href='javascript:history.back();'>[Go Back]</a></body></html>

These are the steps I follow, I have created a collection product and I have my primary and secondary subscription keys.First step was to create an API user when was successful Second step, i created an API key for the API user which was successful. Third step, I created an access token for the user under the collections product subscription. Fourth step, I initiated the requestToPay request but it keeps failing with a 400 Bad Request. Is this an issue currently with the system (going by the error, it is not) or is it specific to me?  

I hope you are doing well. I need assistance with an issue I am encountering while trying to generate an API user in sandbox environment.I have followed all the steps outlined in the documentation: Signup For An Account – Completed Subscribe To Our Products – Completed (subscribed to Collection Widget) Manage Your Subscriptions – Subscription is active, and I have received both the primary and secondary keys Generate API User and API Key – This step is failing  To generate the API user, I am using the following endpoint:POST https://sandbox.momodeveloper.mtn.com/v1_0/apiuserHeaders sent:{  "X-Reference-Id": "<uuid-v4>",  "Ocp-Apim-Subscription-Key": "<Subscription-Primary-Key>",  "Content-Type": "application/json"}Body :{  "providerCallbackHost": "webhook.site"} However, the API returns the following error:Response:{  "statusCode": 401,  "message": "Access denied due to invalid subscription key. Make sure to provide a valid key for an active subscription."} I have veri

I have a mobile application in which people can buy products/services from other users.Is it possible for the sellers, when they signup, to link their mobile money account with this API, so that when the buyers go to buy a product from the seller, they can pay - either with just mobile money too or other payment methods ( I am not sure how that works with this API)  - directly too the sellers mobile money account.Also how would this work with different currencies / countries?Thank you MoMo community!

I am getting remittance transfer bad request error message. my request body is this. any wrong?{  "amount": "600",  "currency": "EUR",  "externalId": "00004335",  "payee": {    "partyIdType": "MSISDN",    "partyId": "56733123450"  },  "payerMessage": "MoMo Market Payment",  "payeeNote": "MoMo Market Payment"}

https://momodeveloper.mtn.com/sandbox/Hello MoMo community,I get the below error message on trying to access the sandboxOops, something went wrong

The documentation is very conclusive but the last step in the process was not yielding me what I wanted and I found a video on youtube which used the reference id (uuid) as a username and the api key as the password. As shown in this image https://postimg.cc/87S93Mrk . There was no token. Please I need to clarify the contents of the last request. I don’t want to say the documentation is wrong but the difference is the video used basic auth in the authorization and followed it as I described earlierResponse ```{    "providerCallbackHost": "string",    "targetEnvironment": "sandbox"}```