What we're doing around card payment disputes at Monzo

Hey! I’m Rika, Monzo’s Lead Disputes Engineering Witch. :sparkles:

Many of you already know me, but for those who don’t, I have been at Monzo now for almost three years. To cut an extremely long story short, I have gone from Customer Operations Technical Specialist back when Monzo was still a prepaid card to building 3D Secure v1, to working on all of our Mastercard card payment systems and new physical cards, and since the beginning of this year I now own the engineering side of card payment disputes.

What I’m about to say is not a formal promise of anything, but I wanted to let the community know what kinds of things I hear about disputing card payments at Monzo along with some of my thoughts around them.

Let’s look at some of the pain points I’ve heard from both this community and from reading customer complaints.

“Reporting a transaction takes too long, I have to wait for support to get back to me.”

We’re looking to solve this with in-app self-serve dispute reporting, which is something that is rolling out slowly right now, beginning with Fraud and Goods & Services disputes. Particularly as we reduce overnight support to urgent queries, it is in our interest to make sure you can file a dispute quickly at any time of any day. My team is not directly building this, but we have a team who normally works on the in-app help screen building transaction help who have been building an information collection flow for us.

“I keep having to explain my case to customer service.”

I’m currently working with my team on rebuilding what we call the “Disputes Lifecycle”. You can think of it like a case management system that tracks a dispute from you sending us the information to the case being fully closed. This already exists, but it is fairly simple and I would like to expand on what it can do.

My ultimate dream is to take all important information out of Monzo Chat where it can get lost in the backlog and put everything together in an easy to understand file of evidence, decisions, and logs of processes.

“Getting a refund takes forever!”

A lot of the time here comes from the 45 days we must wait after a chargeback is filed over the Mastercard network before we find out if you have won or not.

This happens because when a chargeback is filed, we are effectively taking money back from the merchant/acquirer, and the merchant/acquirer then has 45 days to take back the money again. We don’t actually know when you win or lose, just that the timer has expired so the money is yours to keep. At that point, we can actually put it in your account.

In some cases (particularly with fraud), we have a requirement to refund customers “before the end of the next business day after we became aware of the dispute” and we meet that requirement, but we do not currently do this for Goods & Services disputes where we are not bound by that timeline. This is because if Monzo refunds customers, we take on all of the risk for the dispute and with our past setup, that has been too risky.

A recent project of ours has been to integrate with what Mastercard call “Mastercard Collaboration”, it is effectively a system where we can send notifications of disputes directly to merchants, and they can choose to just refund you rather than escalate through chargebacks (which can become extremely expensive for the losing side). We recently launched phase one of this and have a good chunk of disputes being refunded in just a few days. We hope to work on improving this over time.

There are other projects in this area too, by increasing observability across the whole process, we can be more confident in making the difficult decisions that trade risk with customer outcomes.

“I keep having to chase my dispute, it seems like Monzo forgets about it!”

I promise you we are not forgetting about it, once a dispute is recorded it will go through the motions. However, it is totally valid that we don’t let you know about how it’s going and that you have to chase support to find out, being handed from frontline to our Dispute operations team.

There are a lot of smaller things here, but it comes back to the fact that we need to improve our case management system dramatically and make it easier to understand for someone who is not trained in the full Mastercard chargeback manual. From there, we can expose more of it to frontline support staff, and eventually the vision is to show all of the stages to you right in the app.

These are just some of my thoughts, and I don’t want to promise that we will 100% fix all of these in a certain time period, but hopefully you can see the direction things are moving in and trust that if my team changes direction, it will be for good reason.

“Make Money Work for Everyone” is Monzo’s overall mission. That means not just fancy app features, but also making sure that we act in your best interest and support you when things go wrong. Disputes has been worked on by some truly great engineers to get it this far, but has also not really had much true care and long-term vision put into it. I am hoping to change that and make Monzo the best bank to be with if you ever do experience card fraud or issues with a merchant not delivering.

Monzo is already one of the best banks we are aware of in the world for chargeback win rate, but there is still so many exciting things to do.

I will warn up front that almost nothing here is pretty or a fancy app feature. The vast majority of our work is in back office processes that most people won’t experience but for those who do, I hope you will see the impact over the next year or two. If we have done our job right, you won’t notice a thing.

At Monzo, we have been a little scared off from radical transparency recently after getting burned by it a couple of times as priorities changed. This post is a real bet from me that in opening the thinking in this team up, you will be able to understand the direction Card Payment Disputes at Monzo is going in, rather than us promising to hit a series of targets.

I would love to know what you all think if you made it this far! :slightly_smiling_face:


Brilliant! I always love reading the longer, more technical, explanations of behind the scenes at Monzo.


Do disputed transactions get highlighted as such in the feed?

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Disputed transactions are not currently highlighted in the feed.

There are a series of changes to the underlying data model we need to do before that is possible.


This is great work and definitely going to be worthwhile in the long run. Thanks for bringing us along with you.

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This sounds really interesting. I’m not very knowledgeable about banking processes but as a regular forum reader, these all sound like grumbles I’ve seen on the forum at some point.

If these steps go towards helping people get their money back/ feel like they are more in the loop with what’s going on I think that’s definitely a great thing and would ease a lot of frustration or miscommunication!

I always learn so much from your posts on here, even if I don’t understand everything :joy: please do more of them :pray:t3:


Brilliant post. Everything is clearly explained, and it all makes perfect sense to me. It’s great to hear a little more of how some of the processes work behind the scenes, and that you (being Monzo) have a sense of what areas can be improved. :+1:


Rika, as ever, you’re a shining example of boundless knowledge, customer engagement and general awesomeness.

Re the transparency quote. Did this mean that Monzo began to feel that radical transparency is flawed and not appropriate as the organisation grows, or does it mean that it is still desired but staff themselves have withdrawn from that ideal?


This is honestly way above me as one engineer in one niche area of the company, but my personal opinion in my own life outside of Monzo is that being transparent about difficult topics is itself difficult. It is easier to not say anything, but not saying anything leads to things getting bottled up and causing misunderstandings.


Thank you, great answer.

My own opinion is that transparency is radical and should be aimed for, but we shouldn’t beat ourselves up if we fall short (we are all human after all) and that also Monzo should and does retain the right to make a final decision, and customers don’t have the right to hold the bank to ransom on business decisions which have subsequently changed and about which the customers know nothing about.

With an expectation that their bank is being transparent, comes a responsibility upon customers to accept that Monzo is telling the truth and knows what’s best.


I love that you’ve basically highlighted all the concerns I had with my brief experience of the chargeback process. And then you’ve explained great ways to really improve those pain points. :clap::clap:

I do think the help chat is almost too informal. Not the style in which COps communicate through it, more the reliance on this single, never ending group chat. It’s perfect for simple enquiries. But for things like chargebacks and fraud and technical issues I’d much rather a breakaway from that. With an updating timeline graphic and an attempt to manage expectations. I think most people are fine waiting, particularly for things like this, but emulating an instant messaging app kinda makes you expect it to be instant - when it doesn’t really need to have a human constantly reacting to new information and basic enquiries.

However, it sounds like you’re aware and eager to improve that. :+1::heart:


The 45 days makes a lot of sense. I had an issue a few years back where I got charged an extra night instead of a refund for night for a hotel. It took ages to sort but I got the money back… eventually!

I’d love to see screenshots of the self reporting flow 'cause I’m nosey.

Hi @Rika, this sounds great and thanks for setting out the long-term vision. Lots to keep you busy by the sounds of it!

I was a victim of fraud, via PayPal, last year and found the whole process very frustrating (Advice Needed - Fraud with Monzo) - it required me to doing quite a lot of my own digging, after having a chargeback fail, to collate lots of evidence to re-present this back to Monzo.

The key to my eventually successful claim / defence was receiving the Mastercard transaction data report against which Monzo had made the decision (TL;dr it stated my address as the Delivery Address for the transaction which was factually incorrect).

Once I had identified the PayPal transaction ID from this (not as easy as you would think :thinking:), I was able to chase up details directly with PayPal and the merchant, FootAsylum.

As part of this project, is there something here that needs to be factored in around providing evidence to customers where chargebacks are refused / declined? Whilst I’m sure some of these decisions are correct, others (like me) are no doubt going to have decisions made against them incorrectly and need Monzo’s help / guidance to work through this.

Throughout the process I went through, I constantly felt Monzo was battling against me, being unhelpful, not raising important factors (‘hey customer, have you considered you may have been the victim of identity theft?’), and being too trigger happy with raising a formal complaint on my behalf.

The key things I needed to argue my case were the transaction details, someone pointing out the PayPal transaction ID, someone telling me I was a victim of identity theft, and informing me of what I needed to do if I wanted to argue my case. Instead I got a ‘final decision’ :pensive:.

Anyway, I was eventually successful getting my money back but it was anything but a frictionless process - I look forward to your contributions to the end-to-end process and hope I never have to use them :grinning::grinning:


Got one on with Ryanair right now, this is good stuff!

Great post Rika, thank you for taking the time to share this :slightly_smiling_face:

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Just curious, do these “refunds” still count against the merchant if there are too many of them? My concern is that it will allow merchants to essentially get away with what would normally be a high chargeback rate if they were screwing customers over but avoiding scrutiny by just refunding the disputes straight away, relying on the fact that not all customers know how to dispute transactions or have time for it.

The short answer is that if a merchant was doing something like that, there are other ways to bring a case against them.

A high chargeback rate itself is not a great indicator anyway, and there’s no point in investigating a high loss rate because it’s just expensive to deal with, so acquirers and merchants are incentivised to keep those low anyway or their business is severely impacted.

Mastercard very cleverly write their network rules to keep everyone’s incentives aligned so they don’t have to bring the hammer down often because anyone acting against the spirit of the scheme is going to find themselves losing a lot of money very quickly.


Thanks for this insight, and the direction you’re heading sounds really good and well thought through. In terms of transparency and engaging with the community, thank you for taking the time, and this type of post is exactly what I would like more of. I’m not particularly concerned about overly specific feature descriptions or target dates, but having an idea of the issues being tackled, whether or not Monzo is aware of pain points, and very rough timescales (half a year, a year, two years, etc.) is really excellent. Thanks again :raised_hands:


I echo this massively and think the community gets a bad wrap for being impatient.

We just are a nosey bunch and love to hear what cool things monzo are up to, problems faced etc because were genuinely interested in these things.