- Whether or not you want kids.
Disagreeing on this subject isn't necessarily make or break, but if having children is extremely important to one partner and not the other, it could become a larger issue. Especially with biological clocks ticking, this conversation unfortunately has a shelf life and should be discussed early on. If kids are in no way in your future plans, communicate that very clearly.
- Your future goals together.
Do you want to retire early and travel the world with one another, or is your dream to become the ultimate power couple and focus on your careers for as long as possible? Have a chat about what your expectations are for each other (like being parents). Remember, it's all negotiable, too. Maybe you can start your bucket list early together and hold off on kids until when you're both ready.
- Family matters.
In an ideal world, everybody would have in-laws they can love and tolerate, but that's just not the case unfortunately. Any hostility between you (or your SO) and an opposite friend or family member should be squashed before taking the next step. Your relationship will inevitably be affected by these dynamics when they feel like they have to choose between you and blood. If you all can't get along now, it's not going to become any easier later.
Separate or joint accounts, accumulated debt, a prenup, etc. are all important things you should discuss with your significant other. Money can put a huge strain on relationships, and it's often the reason why couples have problems down the line.
- Division of labor.
Both of your opinions on shared household responsibilities will most likely reveal themselves early on in the relationship. But just to be clear, make sure their expectations don't change when your relationship title does. Some people still have very traditional views on what a husband or wife, for example, should be taking care of.
- Making personal decisions.
What's considered off limits and what should always be a joint discussion? Do you want total control or do you not mind when your partner shares their very strong opinions? Keep in mind that marriage usually comes with having to make important decisions as a unit, so communicate clearly what you do or don't mind them having a say in.
- Religious expectations.
If you both come from different religious backgrounds, ask if he or she expects you to convert after marrying. Be vocal about how you feel about holidays and religious obligations, such as not wanting to attend church weekly. And if you two plan to have children, have a conversation about what faith you'd like to raise them in.
This one may be obvious since marriage typically implies monogamy, but some people might be willing to explore the idea of an open relationship. Make it clear that you'd like to discuss the possibility or shut it down completely early on. Or if you or your partner can't imagine committing to one person for the rest of your lives, it's an obvious sign that marriage shouldn't even be in the talks.
- The little things.
A good indication that someone is truly right for you is if they make your relationship seem effortless. You can expect to have a quarrel here and there, but if you bicker about almost everything, it might not work out years later. Not being able to agree on even the most trivial matters is not sustainable for a lasting marriage.