Do I call out DHs lie or keep quiet?

I don't think you need to do anything.
It sounds like your husband is keeping his relationships separate because you and his sister don't get along.
Why would you think that he's only talking to her when you're not there so he can speak badly of you?
I'd find it irritating if my dp was having lengthy conversations on the phone with someone else while I was sat there tbh. Moving to another room to take calls is normal behaviour for us, it's just privacy. With the history, your dh has taken that a step further and only calls his sister when you're not around.
Im not sure why you were asking him about when he last spoke to her. Why does it matter?

It is much, much worse when the behaviour it uncovers is 'he spoke to his sister'...

He has a relationship with her and you need to either accept this and stay or don't accept it and leave.
I can't imagine how i would feel if someone went through my phone and tried to catch me out

So how do you feel about your marriage now @TheDancingHorses Is everything else lovely apart from the SIL thing or is this one of a hundred similar things and you are hanging on my your fingernails.

You don't have to stay with him.

Personally, if this was the only thing, I would let it go. You have accepted there's animosity there and live with it so it's likely he's going to lie about this one thing. If it's another festering turd in an open sewer of other festering turds - bin the feckin lot of them.

Was it the case that you suspected DH had been talking to his sister, because of the way he was talking to you @TheDancingHorses ?
You then looked at his phone after he said he hadn't to confirm it?

I don't think you should have checked (but understand why you did) I think you could have said, and can still say, that the way he is talking to you is unacceptable. Point out that when he has treated you like that previously, it has been prompted by his sister.

It's ok to leave. Dont stay and let this eat away at you. If you really can't move on in your marriage you need to move on outside it. This is no way to live.

I never quite understand why phone-checking is always deemed a worse offence than the behaviour it uncovers.

There are some scenarios that pop up here where you'd really like to hear the other side of things - ie, here, the sister's...

All of this !

how is it possible that he didn’t stick up for you when she was trying to stop you getting married and put his parents off you. HE CHOSE YOU. Regardless of what they said or thought. He chose you. Everyone is not going to be confrontational or make grand declarations. But he keeps his relationship with her siloed and doesn’t bring her up.

theres a mad expectation for men especially to go off at their families when their wives dislike behaviours. Its not realistic and not how most people deal with inter family conflict at all. and worst of all is expects behaviours that they don’t exhibit themselves and more often than not the DH is mild mannered.

your DH has more than likely had multiples chats with all of them.

if he was choosing his family over his wife and kids why are you still married.

In my books, "spying on one's phone" is a much bigger problem than "lying about talking to sister".

So in your shoes, I wouldn't say anything and reflect on how my controlling behaviour leads to my husband feeling like he has to lie about such a trivial thing.

Call me cynical but are ypu married to him because you love him and want to be with him or do you love the sister drama more?

You want him to be comfortable phoning his sister anytime. Complaining You have found out he called her yesterday does exactly the opposite. Its not a serious lie and snooping at phone was worse. I would let it go.

ETA his sister's behaviour to you is awful and him prioritising her at kids birthday and re wedding unacceptable. But on this specific instance yabu if you bring up the lie.

Flip this?

What shitty behaviour by OP? That is a total invention on your part

OP specifically said:
I’m not bothered or interested in what they’re talking about. If anything, it seems weird him only talking when I’m not around, it’s as if he’s hiding things like them talking badly about me.

Why are you so intent on defending OP's H right to talk badly with his sister about his own wife?

Why are you determind to make OP the bad guy in this situation?

Tbh the fact he thinks lying is acceptable in his marriage is pretty damning even without the situation with his sister. Trying to minimise it by calling it " fibbing" doesn't make it acceptable.

OP, I have a sil. She doesn't like me or my sisters. Apparently we are intimidating 😳which (I think) means we work and she doesn't.

If we visit my dB, she doesn't engage, and hasn't for 30 years but that doesn't stop him chatting, visiting, buying us Christmas presents,having a laugh. We don't live in each others pockets, see him about twice a year but we have a strong bond so he treads a fine line but he'd never turn his back on us, nor we on him.
Sounds like the same is true of your dh. Just leave them to it. Be thankful that your dh has more people in his life who love him. That is seldom a bad thing.

I mean this kindly op but you need to move on from the anger about the situation with his sister or leave your marriage. It happened and you chose to marry him anyway but this will eat away at your marriage unless you find a way to deal with your anger. I'm not saying they didn't treat you badly. I wasn't there, but you must have seen enough good in him to stay after that.

Instead put your energy into limiting its impact on you. I go back to traditional forgiveness: agreeing not to take revenge. This is not about forgetting or never feeling but it is about accepting he is allowed his own relationship with his sister. I think contact when you're not around is actually the perfect solution. It has no impact on you. You can just ignore it. Don't ask about her or give her headspace. I recommend guided meditation on forgiveness, acceptance and moving on in these situations. It doesn't have to cost much. There are lots of online options that are very cheap.

Definitely this!

Why on earth do you progress a relationship with this man? Your also mention that she badmouths 'my kids' - presumably they are not her own neices and nephews? Why have you subjected them to this, too?

Honestly, the desperation for dick is just astounding around her sometimes.

@TheDancingHorses while looking at his phone may be wrong I can understand why you did it.
Not only has she caused problems for you but she has targeted your children too. He is putting his sister ahead of his children and some of the replies suggest this is ok? I don't care how close they have been, any parent that puts a relationship with a sibling ahead of their own children would be gone. What ages are the children?
Her behaviour has not only caused problems for you but you suggest that your children have no relationship with their grandparents as a result.
Can you give any examples of what she has done?

I get why you checked his phone. You feel like he has always sided with her and she has tried to destroy your marriage, so you wanted to know if he would lie. He has, and this will make you feel like he is still willing to get in the gutter to side with someone who has been so nasty.
I don’t honestly think I would stay with him, as that is quite low.
there are lots of people on here saying she is his sister and they have a bond - doesn’t he have a duty to his wife and kids first ?

oh come on. Unless someone has done something heinous asking your partner to choose between you and sibling is outrageous.

why do you need to. Why can’t you just dislike each other and not interact. There’s no need for you to be chummy or overly interactive. You say hello frostily once or twice a year at family gatherings and keep it moving. Causing your partner unnecessary strife and trying to make them choose because a sibling “dislikes” you is destructive.

Well the fact that she questions him in the first place sort of gives you the clue.
If OP hasn’t spoken to the SIL in years there’s really no need for her to be bringing SIL into conversation and keeping tabs on when the DH has spoken to her.

It doesn't sound like she was actually interested more than she just wanted to poke the bear and look for an argument if that makes sense.

If this person is someone the OP doesn't like and hasn't for years it seems unlikely she was asking out of genuine interest.

Basically this. You are focusing on the wrong thing. He has allowed you to be abused by his sister over the years so he is complicit in it.

I would be rethinking my relationship to this abusive man and his family. they're all as bad as each other. Stop pandering to the sil by inviting her round ever again. You're a grown woman, you can decide never to see her again, and mean it. Then work on your self esteem and be free of your awful husband too.