英语表达“我说话算话”可以说成“I'll keep my word”(You have my word)或者说“I mean what I say.”

For example:

I promise. I'll be there. I'll keep my word.我保证。我肯定会去的。我说话算话。

当然，如果想让对方说话算话，可直接说：Mean what you say.

下面是关于“Mean what you say”的小短文阅读，一起来看一下吧。

Mean what you say：

If you break your promise, you will ruin your reputation and no one will trust you any more. So whenever we say, "I give you my word" we should mean it. There is nothing worse than to be let down by others because they have not kept their promises.

翻译如下：

说话算数：

如果你违背诺言，你会毁了你的名誉，没有人会再信任你了。所以当我们说“我向你保证”的时候，我们应该认真(对待）。没有什么比失望更糟糕的了，（只）因为他们没有遵守诺言。