Mother's Day cards are a trap, and the trap is this: your mum will claim she wants "nothing fancy, just a nice card", and then she will read that card with the forensic attention of a barrister, file its contents permanently, and quote it back at you in August. The stakes could not be higher. The flowers die. The card is evidence.

So here's the full playbook: funny Mother's Day card ideas, what to write inside them, and the crucial matter of matching the joke to the mum. Written by someone who sells thousands of these every March and has seen what works.

First, know your mum

Every mum sits somewhere on a spectrum between "framed poem" and "would genuinely laugh at a swear word". Be honest about where yours lives. Our funny Mother's Day cards run the full range, and the cute end exists for mums who cry at adverts. The rest of this article is for the funny end, because that's where the good writing lives.

The proven front runners

• The favourite child gambit. Happy Mother's Day From Your Least Disappointing Child is a perennial bestseller for one reason: in every family, someone is legally entitled to send it, and everyone knows who.
• The Nessa. Oh! Mam, If Truth's Be Told, I Loves You I Do. For the Gavin and Stacey household, this is not a card, it's scripture. There's a personalised mug if you want the sentiment to survive the dishwasher.
• The baking truth. Good Mums Let You Lick the Beaters, Great Mums Turn Them Off First. Health and safety as a love language.
• The honest one. Mum, I Thought This Would Be Better Than a Text. It was. It is. She'll keep it.
• The pun. I Herd It's Mother's Day, featuring a cow. Some mums are pun mums. You'll know.

What to write inside

The card front does the joke, the inside does the damage. Twenty openers:

1. Happy Mother's Day from your favourite. We both know. We don't need to say it. I've said it.
2. Thanks for always believing in me, despite the evidence I kept providing.
3. You did an incredible job raising me. I'm the proof, which I appreciate is a mixed message.
4. Happy Mother's Day! I turned out this way entirely on purpose, so technically you succeeded.
5. Thanks for pretending my school artwork was good. I've since seen it. Your commitment was heroic.
6. To the woman who taught me everything, including the specific sigh I now do at my own children.
7. Happy Mother's Day. Sorry about 2009.
8. Thanks for feeding me, raising me, and only occasionally calling me by the dog's name.
9. You're the reason I phone home. Also the person who answers. Efficient.
10. I wouldn't be who I am without you. Discuss.
11. Happy Mother's Day to my first and favourite critic.
12. Thanks for the unconditional love. And the conditions.
13. You always said I could be anything. I chose "a bit much". You handled it well.
14. Happy Mother's Day! This card has no washing in it. You're welcome.
15. To the only person who worries about me at a professional standard.
16. Thanks for the genes. Mostly good. The knees we'll discuss later.
17. Behind every great child is a mum quietly taking the credit she deserves.
18. I love you more than you love a police drama with a strong female lead. Almost.
19. Happy Mother's Day. Your other children send generic regards.
20. Truth be told, I loves you I do. Simple as.

The rules of the day

1. Post early. Mothering Sunday in the UK moves around like it's avoiding someone, so check the date, then subtract a week for the post.
2. Handwrite it. Your handwriting is terrible. She loves your terrible handwriting. It's yours.
3. The joke can be rude, but it must land on love. Every message above is an insult wearing an I Love You underneath. That's the whole art form.
4. When in doubt, go funny. Nobody ever quoted a "wishing you a special day" back at Sunday lunch. The funny ones get read aloud. That's the win condition.

The full range of Mother's Day cards is here: A6, blank inside for your confession, printed in Manchester, envelope included. Choose well. She's keeping it forever, and she remembers everything.