Advice on this almost always supplies a script, which misrepresents what actually happens. Look at your own losses: the friendships you no longer have were, in most cases, never ended. They thinned. Nobody said anything, and there was no moment. That is not a failure of adult communication — it is the form friendship endings take, because friendship has no exit ritual the way a marriage or a job does. Starting from that fact makes everything below more useful than a template would be.
What is usually going on
You want to end it and you want not to be the villain. Two separate goals, and the second one is usually what has stalled you for months. A conversation does not deliver it. People rarely consent to being ended on good terms, and the version where they thank you for your honesty is very nearly a fantasy.
You are looking for permission. Wanting out of a friendship feels less legitimate than wanting out of a relationship, because friendship is supposed to be the easy one. It is not, you are allowed, and no threshold of bad behaviour has to be crossed first. Outgrown is a sufficient reason and always has been.
It is not over, it is the wrong size. Common, and worth checking before doing anything irreversible. Plenty of friendships that feel unbearable at close range are perfectly good at three times a year. Reclassifying costs nothing and reverses easily; ending does neither.
Something happened and you have never said it. If there is a specific injury you have never raised, the friendship has not failed yet — it has not been tested. You are still allowed to end it without saying the thing. You will probably carry it for longer, and it will attach itself to the next friendship that does something similar.
You are waiting for them to do something bad enough. This is what the stalling usually is. Wanting out does not feel like sufficient grounds, so you wait for a justification that would hold up if it were read aloud — and while you wait, the friendship gets quietly worse, because a person who has decided to leave is not a good friend to have. Some people end up engineering the final grievance without ever deciding to. It is worth knowing that you do not need the grievance, and that holding out for one costs both of you a year.
How to do it
Fading, done decently. The default, and it deserves to be done with some care rather than by accident. Reply, briefly and warmly, and stop initiating. Do not manufacture a grievance to make the distance feel earned — that is the part that does real damage, to them and to your own account of yourself. Let it thin. Most people register it quietly and without injury, because they are running the same arithmetic from their side.
Saying it, when the silence would be a lie. Three cases genuinely call for words. You share a group and a silence will confuse everyone in it. They will keep asking, and letting someone keep asking is crueller than an answer. Or something specific happened that they should know about. Then: briefly, in person or in a message that does not demand a reply, with one reason rather than a list, no diagnosis of them as a person, and no offer to explain further. Something like "I've realised I don't have room for this friendship the way I used to, and I didn't want to keep half-doing it." Then stop. The urge to make them agree with the decision is what turns a clean ending into three weeks of argument.
The practical residue. Almost nobody plans for this part and it is where most of the mess actually occurs. Shared group chats, a joint holiday already booked, money owed in one direction, the WhatsApp group you administer, mutual friends' weddings. Deal with each one as an administrative item on its own, separately from the ending and without commentary: leave the chat quietly rather than with a statement, settle the money, answer the wedding question when it arrives. Bundling logistics into the ending is how a decision becomes a six-month negotiation.
What not to do. Do not announce it to the group. Do not do it in anger and call it honesty. Do not hand over the full inventory of grievances — an inventory reads as an invitation to be argued with, item by item. And do not leave the door theatrically ajar if you do not mean it, because the person on the other side will keep checking it for a year.
What it depends on
There are two ways this goes badly, and which one is yours is not random. One person ends friendships by disappearing, because the conversation is genuinely unbearable and vanishing feels like the merciful option — it is almost never received that way. The other writes the long message, with the history and the reassurance and the careful apportioning of blame, because an ending they are entirely responsible for is intolerable; that message is a request to be released, not an attempt to inform.
The Attachment Style test reads the system underneath both: how you handle distance, and what you do when a relationship is about to become a loss. It will not tell you whether to end this friendship. It will tell you which mistake you are most likely to make while doing it, which is the more useful of the two. And if what is actually needed is a limit rather than an ending, the entry on personal boundaries is the better page.