How do you tell adult children you're getting divorced?
Tell them together if you can, tell them early rather than letting them work it out, and resist the pull to explain more than you would to a young child. Adult children are the group most often told too much, and it costs them.
The instinct is understandable. They are grown, they can handle it, and finally there is someone in the family who might take your side. That is exactly the problem.
Why it lands harder than people expect
Parents routinely assume adult children will take it in stride. Many do not, and are surprised by their own reaction.
It rewrites their history. A child who is thirty still had a childhood, and learning that the last years of it were unhappy changes the version they remember. Several describe feeling the ground move under events they thought they understood.
It arrives without the structure younger children get. Nobody arranges anything for them, there is no schedule that acknowledges it, and their friends respond with "well, you're an adult." So they process it alone while being asked to help.
And it lands during their own lives: their careers, their marriages, their small children. A parental divorce at thirty-five can be genuinely destabilizing at a moment they are supposed to be the stable one.
The three things to avoid
Do not tell them the details. This is the big one and it is very hard. They can understand an affair, a betrayal, a decade of resentment, and understanding it is not the same as being able to hold it. Telling one parent's version enlists them, and it damages their relationship with the other parent, permanently in some cases.
They may ask directly. You can decline warmly: that is between the two of us, and you do not have to hold it.
Do not use them as a messenger or a go-between. Adults get recruited for this far more than children, because it seems reasonable. "Can you ask your mother about the house." It is the same harm, and it does not stop when they are grown.
Do not lean on them as your support. One conversation is fine. A pattern where a child becomes a parent's primary emotional support inverts the relationship and is hard to undo. That is what a therapist and your friends are for.
What to do instead
Together, and in person if it is possible. A single account from both of you prevents the version where they hear two different stories and have to reconcile them.
Tell them before anything visible happens. Learning it from a relative, a social media post, or a moved-out parent is a separate injury on top of the news.
Say what is actually changing for them: the house they grew up in, where holidays happen, what happens with grandchildren. These are the practical questions they will not ask immediately and will worry about.
Say plainly that you are not asking them to choose. Then behave that way, which is the harder part.
Give them time. They may be angry, or take a side, or go quiet for a while. Most of that settles.
Holidays and grandchildren
The two friction points, and worth naming early rather than discovering them in December.
Adult children end up managing the logistics of divorced parents for decades: who comes to what, who sits where, whether both can be at the same wedding. The parents who make this easy get more of their children's time, without having to ask for it.
If there are grandchildren, be explicit that both of you intend to stay involved and that you will not put your child in the middle of arranging it.
If they are somewhere in between
Late teens and early twenties are the hardest case: legally adults, emotionally still very much your children, and often away from home where nobody is watching how they are doing. Tell them as you would a younger child, with less detail than you think, and check on them more than they ask you to.
Telling your children covers the conversation with younger ones, and much of it applies here with the volume turned down.
Adult children have no role in the divorce itself and often end up carrying a great deal of its emotional weight. If one of them is struggling with it, a therapist of their own is a reasonable suggestion rather than an overreaction.