"Maintain our contact" or "stay in contact"

Question

Which of these phrases sound more natural to a native speaker in a professional/formal letter?

1. I would like to maintain our contact
2. I would like to stay in contact

I would like to express the desire to keep the recipients contact details in case of future opportunities for cooperation. To me, "stay in contact" sounds like I am pursuing an ongoing, active exchange.

Answer 1

Google Books Ngram viewer shows that of the four phrases most likely to be used in this context, by far the most popular is stay in touch.

Next comes maintain contact, followed far behind by stay in contact, with maintain our contact in last place.

Although stay in touch has achieved its popularity only over the last 60 years, it has soared into top position. It's slightly more informal than maintain contact but would not sound out of place in a formal letter.

So I would go with either of the first two options although there is nothing wrong either idiomatically or grammatically with the last two.

It's really just a matter of preference.

https://books.google.com/ngrams/graph?content=stay+in+contact%2Cmaintain+contact%2Cmaintain+our+contact%2Cstay+in+touch&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cstay%20in%20contact%3B%2Cc0%3B.t1%3B%2Cmaintain%20contact%3B%2Cc0%3B.t1%3B%2Cmaintain%20our%20contact%3B%2Cc0%3B.t1%3B%2Cstay%20in%20touch%3B%2Cc0