Source of Funds – how to prove where your money came from

The money you got in your account? All legal. You earned it, you paid tax on it, you moved it – and then the bank suddenly asks you to prove all three. It’s a strange thing to be asked about your own money, and a surprisingly hard thing to answer on the spot, especially when the request arrives with a deadline attached. But a source-of-funds check isn’t an accusation of something you didn’t even do. It’s a paperwork problem, and paperwork problems have solutions. We’ll go over everything here.

What is Source of Funds (SoF)?

Source of funds means the origin of a specific sum of money – the money behind this transfer, this deposit, this purchase. Not your overall wealth in general. Not proof that the money is in your account today. Just one question: where did this specific sum of money come from, and can you show it?

Banks ask because the law tells them to, not because they accuse you of something. Knowing who you are says nothing about whether the money moving through your account makes sense. So when a situation looks higher-risk, an EU bank has to find out (Article 18) where the funds came from before it lets the transaction through.

The bank isn’t really asking if your story is true, it’s asking if you can document it. It’s just an international standard. A compliance officer can’t just take your word for it, file it away, and defend that to a regulator two years later. They need something they can check: a contract, a payslip, a statement with dates and amounts that match what you told them.

That’s why honest people with legal money still get rejected. Not exactly because anyone doubts them, but because the paperwork doesn’t prove what they’re saying, or maybe the paperwork is just not there.

Source of Funds vs Source of Wealth: what’s the difference

Source of funds vs source of wealth often get mixed up constantly, but the difference is simple:

• Proof of source of funds is about one sum – where did the money for this transfer come from?
• Source of wealth is about everything you own – how did you build it up?

Here’s an example. You transfer €5,000 and say it’s your salary. You show your employment contract and a statement with the salary arriving. That’s it – source of funds, and case is closed.

Now transfer €200,000. The bank still asks where the money came from, but a payslip doesn’t explain it anymore. Nobody on a normal salary has €200,000 lying around by accident. So the question gets bigger: how did you build up that much? That’s the source of wealth. Answering it usually means going back years – a property you sold, a business you owned, an inheritance, savings, etc. The approach to these checks is risk-based. 

Most of the time you’ll only face a source of funds check. Source of wealth comes up when the sums are very large, when your profile is flagged as higher-risk, or when your answer about one transfer doesn’t cover the whole amount.

And Proof of Funds is a third thing

Yes, Proof of Funds and Source of Funds are two different things. 

Proof of funds shows the money is there. It’s usually a bank letter or statement confirming you hold a certain amount right now. Sources of funds show where that money came from.

You often need both, especially when buying property. The seller wants to know you can actually pay. The bank or notary wants to know the money is clean. One question is about the balance, the other about the history – and they’re not mutually exclusive. You can read more about Proof of Funds here. 

When and why a bank asks about source of funds

The request doesn’t come out of nowhere – usually something sets it off:

• You open an account and put in a very large first deposit
• Money arrives from abroad, especially from a higher-risk country
• A transfer doesn’t fit what the bank knows about you
• You’re buying property, and the bank or notary needs the money cleared first
• You’re a politically exposed person, or close to one
• Your business or ownership structure looks complicated on paper

The reason behind all of it is the same – EU banks have to watch what moves through their accounts and report anything that looks suspicious. If a situation looks higher-risk, they can’t just process the payment and hope for the best. They have to find out where the money came from first.

This isn’t only an account-opening thing – the checks run for as long as you bank there. A request can arrive years into a completely normal relationship.

And nothing has to have gone obviously wrong. One transfer outside your usual pattern is enough.

How much money triggers a check?

EU rules do set thresholds (Article 19). They trigger identity checks, though, not source of funds questions:

€10,000 – one-off transactions, from July 2027 (€15,000 under current rules (Article 11))

€3,000 – cash transactions

€1,000 – one-off crypto transactions at a licensed provider

Cross one of these and the provider has to identify you properly. Nobody automatically asks where your money came from. Source of funds is different – it follows risk, not size. The real question is whether the money fits you.

Let’s say you earn €2,000 a month and deposit €9,000. You’ll be asked about it. Now take a business owner with €50,000 moving through the account monthly. They can send €40,000, and nobody cares because it’s just natural for their profile.

Don’t plan around a number. Plan around whether the transfer looks normal for your unique case. If it doesn’t, have the documents ready before you send it.

What documents prove source of funds

The answer depends on where the money came from. A salary needs different paperwork than an inheritance, and an inheritance needs different paperwork than a property sale. Below is what banks usually want for each of the most common sources – find yours and start there.

Salary and employment income

The most common source, and the easiest to prove. What source of funds documentation banks usually want:

• Your employment contract, showing your employer and salary
• Recent payslips, usually the last three to six months
• Bank statements showing the salary arriving
• A tax return or income certificate, if you have one

The statements do most of the work – they show the money coming in on a regular date, from a named employer, in the amount your contract promises. That’s exactly the kind of reliability banks love to see. And what if you’re self-employed or freelance? It’s pretty much the same: tax return, invoices, and client payments landing in your account.

One thing to remember – if the money is savings built up from salary over years, recent payslips won’t cover it. You’ll need statements going back far enough to show it adding up.

Sale of property or a vehicle

This one is easy to prove as well, because a sale leaves an official trail. Here’s what banks may ask:

• The sale contract – what you sold, to whom, for how much
• Proof the ownership changed hands: registry entry, notarial deed, or vehicle registration
• Bank statements showing the buyer’s payment arrived
• A valuation, if the price looks odd for the asset
• Tax paperwork, if the sale was taxable

The numbers have to match too (Article 13(1)(d)). If the contract says €80,000, but you actually got like €95,000 in your account? The bank will ask about the difference.

And don’t forget about the date. If you sell something in, say, March, and get money in November? It sure looks weird, and the bank will ask for an explanation. 

One important thing to keep in mind – if the buyer paid cash and you deposited it yourself, the trail breaks. The contract proves you sold something. It doesn’t prove the cash in your hand came from that sale.

Inheritance

These cases are usually well-documented because inheritance goes through official channels (Article 13(1)(a))anyway, so proving something should be easy. What banks usually ask for:

• The inheritance certificate, notarial deed, or probate document
• The will, if there was one
• A death certificate
• Bank statements showing the money arrived
• Tax clearance, if the inheritance was taxable

Two things tied to cases most people have no idea about:

• If several heirs split the estate, show only your share. A paper saying the estate was worth €400,000 doesn’t explain why you got €100,000.
• And if you inherited property instead of cash, you need two sets of documents. One shows the property became yours, and the other shows how you sold it.

Gifts from family or friends

The hardest common source to prove, and the one banks reject most often. A gift leaves no automatic paper trail because money just moves from one person to another, and nothing about the transfer explains itself. Here’s what can convince banks:

• A written gift declaration – amount, date, who gave it, and a clear statement that it isn’t a loan
• The giver’s ID
• Bank statements from both sides, showing the money leaving and arriving
• Proof of where the giver’s money came from

The bank isn’t only checking that someone gave you money, it’s also checking that their money was clean too (Recommendation 10). So your parent, your friend, whoever it was, has to document their own source of funds as well. And if they handed you cash that you deposited yourself, there’s nothing to trace at all – which is the worst case here.

Business income, dividends, company sale

This one is the most complex source, because you have to explain two things: that the company’s money is clean (Article 13(1)(b)), and that it reached you through a proper route. Here’s what banks usually want to see:

• Company registration documents and a register extract
• Proof you own or owned a share of it
• Financial statements or accounts
• A dividend resolution, if that’s how you were paid
• The share sale agreement, if you sold the business
• Company and personal tax returns
• Bank statements showing the payment arrives

Dividends need to be properly declared and taxed, not just moved from the company account to yours because both belong to you. Money sliding between the two looks like mixed personal and business funds, and that’s a red flag for banks. And if you sold the company, the contract has to match what landed in your account – installments or escrow included, since those explain any gap.

Savings, loans, investments

Savings are often the hardest to prove, because they built up slowly. A statement showing €80,000 in your account proves the money is there, not where it came from. You’ll need statements going back far enough to show it accumulating, plus proof of the income that fed it – usually salary or business documents from those years.

Loans are easier – the bank wants the loan agreement, the lender’s details, and statements showing the money arrives. If the lender is a private person rather than a bank, expect the same treatment as a gift – they’ll have to document their own source of funds too.

Investments need brokerage or platform statements, confirmation of the sale that released the money, and ideally a history of what you invested and when.

With all three, the bank is really asking one thing: does this amount make sense (Article 13(1)(d)) for someone with your income? 

Crypto as a source of funds

This one is the trickiest source of all, because banks want two stories: where the crypto came from, and where the money to buy it came from. Here are the proofs banks want to see:

• Transaction history from the exchange (Article 19), or a source of funds report
• Wallet addresses and the trail between them
• Bank statements showing money going to the exchange in the first place
• Proof of the sale or conversion that turned it back into euros
• Tax declarations covering the gains, where they applied

An exchange statement alone satisfies nobody. It shows you held crypto and sold it, but not how you got it. If you bought coins with your salary in 2019, the bank wants to see the salary and the payment to the exchange.

And there are two cases that make things even trickier:

• Coins bought years ago on an exchange that no longer exists mean reconstructing records that may no longer exist. 
• Crypto bought with cash or peer-to-peer leaves no independent trail at all.

The core principle of Source of Funds documents

A statement showing €50,000 in your account proves almost nothing – it shows the money is there, not where it came from. What proves the source are the contract that created the money, and the statement showing that exact sum arrived on that date.

Three things have to be consistent:

• Amounts match (Article 13(1)(d)). A €60,000 contract and a €75,000 deposit are two different things until you explain the extra €15,000.
• Dates make sense. Selling something in March and getting money in September is fine as long as you can explain why. 
• Documents don’t contradict each other. If your tax return says one thing and your contract says another, the bank believes neither.

How to prepare your document package, step by step

1. Ask what exactly they need. Before getting any documents, get the request in writing: which transaction, which period, which documents. Banks often accept several alternatives.
2. Identify the source. “Savings” isn’t a source, but salary saved over four years is. If the money came from more than one place, treat each part separately.
3. Collect the primary documents. The contract, certificate, or agreement that created the money – whatever is suitable and whatever the bank asked you to provide. This proves the event happened, and it has to come from an independent source (Article 13 (1)(a)), like a notary, an employer, a registry – not from you.
4. Add the banking trail. Statements showing the money leaving and arriving to you. Amounts and dates should line up with the primary document.
5. Cover the gaps. Anything that doesn’t match current documents needs explaining before they ask – this will save you lots of time.
6. Add tax documents where they exist. A declaration showing the income was reported is one of the strongest things you can include, because a second authority has already seen it.
7. Check the technical quality. Full pages, all corners visible, nothing cropped, no screenshots where an official statement is expected. Be sure to get certified translations for documents not in the bank’s language.
8. Submit before the deadline. If you can’t gather everything in time, say so in writing and ask for an extension. Silence may get treated as non-cooperation.

How long does a source of funds check take?

The depth of the check scales with the risk, so the timeline scales with it too. As a rough guide: a straightforward case with complete documents usually takes about 5 to 10 days. Several funding sources, or anything higher-risk, can extend it to two to four weeks.

Incomplete paperwork can greatly extend the waiting period too. Every missing document restarts the clock – they review, they ask, you send, they review again, all until everything’s good enough. 

Which is the argument for over-preparing. Sending everything at once, with a covering letter that explains the gaps, is almost always faster than sending the minimum and waiting to see what they come back with.

Why a covering letter is important

Unfortunately, documents don’t explain themselves. If you send eight files with no note, someone at the bank will have to figure out what they mean and how they add up. A covering letter does that work for them. Don’t overdo it – about half a page is enough. It should answer four things:

• What happened – the event that produced the money
• When – dates that match the documents
• How much – the exact amount, and where any difference comes from
• What proves it – which attachment supports which part

Writing something like “Attachment 3 is the sale contract, attachment 4 shows the payment arriving on 14 March” – it saves the reviewer from matching things up themselves. It saves everyone’s time. 

There are a few things you shouldn’t do – no arguing that the request is unfair, no story about how rough the year has been, etc. A compliance officer needs a clean chain of events they can file and defend later – give them that and nothing more.

Why banks reject the documents

There are some popular mistakes a lot of people do, resulting in rejections:

• Cash with no trail. Money you deposited yourself can’t be traced back to whatever produced it. This is one of the most popular mistakes. 
• Amounts that don’t match. One document says one number, the deposit is completely different, and nothing explains the difference.
• Screenshots instead of statements. You need to provide an official PDF from the bank or exchange, not a photo of your phone.
• Vague “gifts”. The gift with no declaration, no ID, and no proof of where the giver’s money came from will cause questions.
• Third-party payments. Money arriving from someone unconnected to the transaction you described.
• Documents that are too old. A contract from eight years ago with nothing connecting it to today’s balance.
• Crypto with no purchase history. An exchange statement showing the sale but nothing showing how you acquired the coins.
• Missing the deadline (Article 14(4)). Going quiet looks like non-cooperation, and banks don’t like it. Even if you didn’t mean it. 

What happens if you don’t prove it

Consequences usually come in stages:

1. The transaction stops. The first and most common outcome – the transfer doesn’t go through, or the incoming payment sits unavailable while the bank waits.
2. The account gets restricted. Outgoing payments are blocked, the card is frozen, and online banking is limited. The money is still yours, but you can’t move it.
3. The relationship ends. If the bank can’t complete its checks, EU rules leave it no choice (Article 14(4)): it has to refuse the transaction and can terminate the relationship entirely. That means account closure, and it’s not really good, because the next bank will ask why the last one let you go.

What happens to your documents afterward?

Banks don’t keep them forever, but they can’t delete them straight away either. Under EU anti-money-laundering rules, they must retain (Article 40) your identity and transaction records for five years after your relationship with the bank ends. Some countries extend that. The point is that if a regulator or investigator reviews the file later, the evidence is still there.

Throughout that period, GDPR (the EU’s data protection law) applies. Your documents can only be used (Article 5) for the purpose they were collected for, not marketing or anything unrelated. They have to be kept securely, and deleted once the retention period expires.

You keep your usual data rights too. For example, you can ask what a bank holds about you. But if the file relates to a suspicious activity report, the bank may be legally barred from telling you. That’s just a rule, and it’s the reason a bank sometimes can’t answer even a reasonable question.

What clients from Ukraine should know

Ukraine is on many banks’ higher-risk lists, so transfers from there get enhanced checks by default. Wartime currency controls make it harder still – NBU rules limit when and how money can leave the country, so people take a less obvious route, and that route looks unusual to the receiving bank.

Three things to keep in mind if you want to transfer money from Ukraine to the EU:

• Documents need translating. Ukrainian contracts, certificates and tax returns usually need certified translation. 
• Some gaps are common and explainable. Documents lost in occupied territory, registries you couldn’t reach, employers that no longer exist. Say so in your covering letter. If you explain the gap, the bank may offer a workaround. If you stay quiet, it probably won’t. 
• Cash savings are the hardest case. Money kept at home for years and then deposited abroad has no trail at all. 

If this applies to you, we covered it in why EU banks block transfers from Ukraine.