If you’ve been in a long-term relationship, chances are that money has been swapped between the two of you many times. Whether it’s movie tickets, Uber rides, plane tickets, restaurant dates, petrol, the quick e-Wallet every now and again, most partners take turns paying these bills.

With these kinds of amounts, no-one really keeps track of who owes what, but at some point, your partner may want to borrow real money from you – significant amounts that you might not write off so easily. A large loan can lead to conflict in your relationship if you don’t handle it the right way.

Numerous studies have shown that financial disagreements and tensions are among the most common strains in intimate relationships. And even worse, research has shown that arguments couples have about money tend to be a lot more intense than those about other issues, and are often the most likely to remain unresolved.

READ MORE: Having the money conversation with your partner – without fighting

“Early on in a relationship, many couples discuss their views on marriage, children and where they want to work and live. Unfortunately, couples rarely sit down together to talk about their financial beliefs and goals,” writes the American Psychology Association in a report.

“Having an understanding of your partner’s beliefs can help resolve conflict and set the stage for healthy discussions about your joint finances, “ it concludes.

Here are the four essential things to consider when lending money to your partner.

Make sure you can live without that money
Stefanie O’Connell, author of The Broke and Beautiful Life: Small Town Budget, Big City Dream, writes that you should never lend someone more money than you’re prepared to lose, no matter how in love you are or how convincing they are about their ability to pay you back.

“You’re madly in love, your significant other is an honest and trustworthy person and the circumstances of the loan are such that you are confident that you’re going to get your money paid back ASAP,” O’Connell writes.  “Even so, the rule applies”.

Too often, we avoid having open discussions about money because we assume that we’re on the same page as the other person.

Put everything in writing
Make sure that you both sign a promissory note stating the amount being borrowed, the terms of the loan agreement and the payment timeline. It’s essential to put all the details in writing.

O’Connell says that the reason a promissory note is important is so that both parties have a very clear understanding of what the expectations are from both sides.

“Too often, we avoid having open discussions about money because we assume that we’re on the same page as the other person. But we’re not. And by the time we figure that out, it’s usually too late,” she writes.

Many people may feel uncomfortable about his kind of formality, and if this is the case, a simple conversation over email detailing the amount of the loan, the intended purpose of the money and the repayment terms will also suffice.

You are allowed to say no

A good relationship is based on, among other things, honesty. It’s crucial to be honest about your financial position and, if you are unable to help without compromising your own financial stability, it’s okay to say no.

READ MORE: Is it a good idea to open a joint bank account with your partner?

Let it go
This last tip is linked to the first. For your sanity and peace of mind, as well as the health of your relationship, once you have decided to lend your partner money, don’t constantly bring it up. As long as you know that you and your partner are clear about the expectations and terns, let it go.