A lender should keep four kinds of evidence: proof the loan was agreed, usually the signed agreement; proof the money was actually handed over, such as a transfer slip; a record of every repayment received; and the messages around the loan, including reminders and any changes to the terms. Together these cover every question a dispute could raise.
Think of it from the opposite direction: if the borrower one day said I never borrowed that, or I already paid it all back, what could you put on the table? Every item in this guide exists to answer one of those two sentences. Keeping this evidence is not a sign of distrust, it protects the borrower too, since a lender with clear records cannot honestly claim more than is owed.
Proof the loan was agreed
The anchor document is a signed loan agreement stating the parties, amount, repayment plan, and interest, with signatures from both sides. Keep the original if it is paper, and a complete final PDF if it was signed electronically, along with the messages in which it was exchanged. This is the document that establishes there was a loan at all, with terms, rather than a gift or a vague favor.
If the loan started informally, the gap can still be closed afterward with a signed debt acknowledgment, in which the borrower confirms the amount owed and the plan to repay it. Failing even that, preserve whatever shows agreement: the chat where the borrowing was discussed, a voice message, an email. Something contemporaneous and specific always beats reconstructed memory.
Proof the money was actually handed over
An agreement proves a promise; it does not prove the money moved. That is the transfer record's job. For bank transfers, PromptPay, and e-wallets, save the slip or confirmation showing the date, amount, and recipient, and keep the bank statement line as backup, since app screenshots can be lost when phones change. The name on the receiving account matters: money sent to the borrower's own account is much easier to connect to the loan.
Cash is where lenders most often end up exposed. If you hand over cash, have the borrower sign a dated receipt for the amount at the moment of handover, or at minimum send a same-day message, handed you the 15,000 baht in cash just now as we agreed, and keep the reply. If someone else's account receives the money, for example the borrower's spouse, get the borrower to confirm in writing that this counts as the loan being delivered.
A record of every repayment
Repayment records answer the second dangerous sentence, I already paid it all back, and they protect the borrower just as much, because they stop an honest lender from double-counting. Keep a simple running table for each loan: date, amount received, method, and remaining balance after the payment. Update it the day money arrives, while the details are fresh.
Say Nok lent her cousin 30,000 baht, repayable at 2,500 per month. Fourteen months later, with a skipped month, one partial payment, and one month paid double, nobody's memory holds that history accurately. Nok's one-page table, backed by the matching transfer slips, settles in thirty seconds what could otherwise become a family argument. For cash repayments, give the borrower a signed receipt each time and keep a copy, those receipts are the borrower's protection and your record simultaneously.
- A running log per loan: date, amount, method, remaining balance
- Transfer slips or statement lines for every repayment received
- Copies of signed receipts issued for any cash repayments
- Notes of anything unusual: partial payments, overpayments, skipped months
- A confirmation message to the borrower when a payment is received and when the balance changes
Messages, reminders, and acknowledgments
The conversation around a loan is evidence in its own right. Messages where the borrower asks for time, apologizes for a delay, or confirms a balance are all acknowledgments of the debt, and in some places they can matter for limitation periods too. Keep reminder messages you send and the replies you receive, they show you followed up seriously and how the borrower responded.
Export chat threads rather than trusting the app to keep them forever, and save emails and voice messages outside the original platform. A practical habit is a yearly balance confirmation: a short message stating the remaining balance and asking the borrower to confirm. It keeps both sides synchronized and quietly refreshes your evidence.
Changes to the loan
Loans between people evolve: a due date slips, an amount is renegotiated, a lump payment settles part early. Every change agreed only verbally is a future dispute about what the current deal actually is. Record each change in writing, a short signed amendment for significant changes, or at minimum a message stating the new terms with a confirming reply from the borrower.
Keep the versions in order, the original agreement plus each dated change, so the history reads cleanly. When the loan ends, close it in writing with a final payment confirmation stating the debt is fully repaid, and keep that document permanently. A loan that ends without a written closure has a way of coming back.
Organizing and storing it all
Evidence you cannot find is evidence you do not have. Keep one folder per loan, digital, physical, or both, containing the agreement, the disbursement proof, the repayment log, receipts, exported chats, and any amendments. Merging the core documents into a single chronological PDF makes the whole story shareable in one file if you ever need to show it.
Store copies in at least two places, for example on your device and in a personal cloud folder, so one lost phone cannot erase a loan's history. Keep everything until well after the final payment, several years is a sensible habit since time limits for claims vary by country, and keep the closure document longest of all.
Checklist
- Signed loan agreement or debt acknowledgment, original and digital copy
- Transfer slip, statement line, or signed cash receipt proving the money was handed over
- Running repayment log with dates, amounts, and remaining balance
- Proof of every individual repayment, including receipts for cash
- Exported chat threads and emails about the loan, including reminders and replies
- Written record of every change to the terms, signed or confirmed in chat
- Final payment confirmation once the loan is fully repaid
- All of it in one folder per loan, backed up in a second location
Common mistakes
- Keeping the signed agreement but no proof the money was ever actually transferred.
- Accepting cash repayments with no receipts, leaving the balance to memory on both sides.
- Letting repayment records live only in a banking app that gets replaced with a new phone.
- Agreeing changes verbally so the paper terms no longer match the real deal.
- Deleting old chats during a phone cleanup while the loan is still outstanding.
- Scattering evidence across apps and drawers with no single folder per loan.
- Ending the loan with a verbal all settled instead of a written final confirmation.
Frequently asked questions
How long should a lender keep loan evidence?
Keep everything until well after the loan is fully repaid, and several years beyond is a sensible habit, since the time limits for bringing claims vary by country. The final payment confirmation is worth keeping permanently as your proof the matter is closed.
What is the single most important piece of evidence?
The pairing of a signed agreement with proof the money moved. Either alone has a gap: the agreement without a transfer record invites the claim the loan never happened, and a transfer without an agreement invites the claim it was a gift.
Do digital copies count, or do I need paper originals?
Digital copies are widely accepted and are essential as backups, but keep any paper originals you have, especially signed documents, since originals carry the most weight if a signature is ever questioned. The strong position is both.
Should I give the borrower receipts for their payments?
Yes, especially for cash. A receipt protects the borrower from paying twice and protects you by creating a signed, dated record of exactly what was received. Keep a copy of every receipt you issue, they double as your repayment log's supporting documents.
What evidence matters most for a cash loan?
A signed receipt from the borrower at handover, a same-day written confirmation in chat, and if the amount is large, a witness. Cash creates no automatic record, so the documents and messages you create yourself are the only trail that will exist.
The borrower repays through a relative's account. Is that a problem?
It can blur the trail. Ask the borrower to confirm in a message that the payment from that account counts toward their loan, and note it in your log. The clarification takes one minute now and prevents an accounting dispute later.
Is keeping all this evidence insulting to a borrower I trust?
Framed properly, it is the opposite. Clear records mean the borrower can never be asked to pay more than is truly owed, and receipts are their protection as much as yours. Most people accept record-keeping easily when it is presented as fairness for both sides.
This guide is general information, not legal advice. Legal requirements vary by jurisdiction, transaction type, and individual circumstances.