BIFF Method: How to Respond to Hostile Co-Parent Messages
Your phone buzzes with a text from your ex: "I can't believe you let Emma stay up past her bedtime AGAIN. This is exactly why I worry about her being at your house. You clearly don't care about her wellbeing."
Your fingers hover over the keyboard. You want to explain that Emma had a school project due, that bedtime was only 30 minutes late, that you're actually an excellent parent despite what they think. You want to list all the times they've bent the rules. Stop. Put the phone down.
This is the moment where co-parenting either escalates into a documented conflict or gets handled with the grace that protects everyone involved, especially your kids.
Enter the BIFF method.
What is BIFF?
BIFF stands for Brief, Informative, Friendly, Firm. It's a communication strategy developed by Bill Eddy at the High Conflict Institute specifically for dealing with high-conflict personalities. The framework keeps you from getting sucked into arguments that go nowhere while maintaining a professional record of communication. The goal isn't to win the argument or change your co-parent's mind. The goal is to respond appropriately, document your side, and move on.
The Four Components
Brief
Keep responses to 2-5 sentences maximum. Every extra word is an invitation to dissect, misinterpret, or argue. Long explanations make you look defensive. They also give the other person more ammunition.
Let’s hope that your communication stays between you and your ex - but worst case, you're writing for an audience of another potential reader down the line, a family court judge who has 30 seconds to scan your exchange. Think of it this way - what do they need to see? That you responded calmly and stuck to facts.
Informative
Provide only the information necessary to move forward. Strip out opinions, emotional reactions, references to past incidents, or any commentary on their behavior or parenting.
Ask yourself: what does the other person actually need to know right now? That's it. That's the message.
Friendly
This doesn't mean warm. It means neutral and professional. Use phrases like "Thanks for letting me know" or "I appreciate you sharing that concern." These aren't about being genuine friends. They're about removing the emotional charge from communication. A friendly tone denies the other person the fight they're looking for. There's nothing to grab onto, nothing to twist into evidence of your hostility.
Firm
End the conversation. State what you will do, not what they should do. Avoid questions that keep the dialogue open. The firm part is what stops the endless back-and-forth. You've said your piece. There's nothing left to discuss. Move on with your day.
BIFF in Action
Here are real scenarios with both typical reactive responses and BIFF alternatives.
Scenario 1: The Late Pickup Accusation
Hostile message: "You were 20 minutes late dropping off Jacob today. This is unacceptable and I'm documenting every instance for my attorney."
Typical response: "I was 15 minutes late, not 20, and it was because of an accident on Highway 9 that backed up traffic for miles. Maybe if you weren't always watching the clock and trying to catch me in something, we could actually co-parent like adults. I've been on time the last 30 pickups but you conveniently forget that."
BIFF response: "There was unexpected traffic on Highway 9 today. I'll plan for extra time going forward. Jacob had his backpack and homework."
Scenario 2: Last-Minute Schedule Change
Hostile message: "I need to switch weekends because I have something important come up. I'm taking the kids this weekend instead of next weekend."
Typical response: "No. We have a custody schedule for a reason. You can't just decide to change things whenever you feel like it. I already made plans with the kids and they're excited. This is so typical of you to only think about yourself."
BIFF response: "I have plans with the kids this weekend that can't be rescheduled. I'm available to discuss trading specific days if you let me know what works on your end by Wednesday."
Scenario 3: Parenting Criticism
Hostile message: "Madison told me you let her watch TV during dinner. We agreed on no screens at meals. Can you actually follow through on something for once?"
Typical response: "First of all, it was ONE time and it was a nature documentary for her science project, not some mindless show. Second, YOU let her have her iPad at breakfast last month when I picked her up, so don't lecture me about screen rules. Maybe focus on your own parenting instead of constantly criticizing mine."
BIFF response: "Thanks for the reminder about our screen agreement. I'll make sure meals stay screen-free going forward."
Scenario 4: Money Dispute
Hostile message: "You owe me $180 for half of Evan's cleats and team fees. I shouldn't have to chase you down for this. Just Venmo me the money today."
Typical response: "I already paid for his summer camp AND his new jacket without asking you for half. If we're going to nickel and dime each other, I can send you an invoice for everything I've covered. Also, you didn't ask me before signing him up for travel team, so I'm not sure why I should pay for a decision I wasn't part of."
BIFF response: "Please send me the receipt and I'll review our expense agreement. I can get you a response by Friday on my portion."
When BIFF Isn't Enough
The BIFF method works for typical high-conflict communication. It doesn't work for everything.
If your co-parent is threatening you, harassing you with dozens of messages, or violating court orders, I’m not saying BIFF will be the cure-all. Document everything, stop responding, and consult with your attorney.
There are situations where the best response is no response. If someone is trying to bait you into an argument about something that doesn't require a reply, you don't owe them one. Silence is also a perfectly acceptable communication strategy.
Why a Coparenting App Makes This Easier
Here's the thing about using text messages for co-parenting: they disappear into long threads, they can be deleted, screenshots can be accused of being doctored, and there's no neutral record.
CoParent Compass creates a documented communication trail that can't be altered after the fact. Every message has a timestamp. Nothing can be deleted by either party. If you ever need to show a judge your communication history, you have a clean, professional record that shows you used BIFF principles while the other person didn't.
The platform also removes communication from the emotional battlefield of text messages. There's something about texting that makes people feel like they can fire off whatever thought pops into their head. Moving conversations to a dedicated co-parenting platform adds a layer of formality that often improves behavior on both sides. Plus, when messages live in your Timeline alongside schedule changes, expense records, and document uploads, you have context. You can see patterns. You can prove that you've been professional and responsive even when the other person hasn't.
Final Thoughts
Learning to use BIFF responses feels unnatural at first. You want to defend yourself. You want to be understood. You want the other person to acknowledge that they're being unreasonable.
Let that go.
BIFF isn't about being right. It's about being smart. It's about protecting yourself and your kids from endless conflict. It's about creating a record that speaks for itself.
The best part? After a few weeks of BIFF responses, most high-conflict co-parents either calm down or give up trying to engage or trigger you in arguments. When there's nothing to fight about, the fight loses steam.
Your kids deserve parents who can communicate without drama. BIFF gets you there.
Ready to take co-parenting communication out of the chaos? Try CoParent Compass (free trial period!) and see how documented, professional communication changes everything.