Most important is the context in which Neutraface and the serif will be used. What is your project? Who is your audience?

If Neutraface is the display face, a modern (didone) would be a good text complement.
Or possibly a non-geo slab serif, e.g. Archer or Bodoni Egyptian.

If Neutraface is the text, you could try matching a modern where the hairline corresponds to the weight of the text monoline.
To see this effect, set up some 72 pt text in Scotch Modern Display in the type tester, and put the window next to a showing of Neutraface Light

But really, any true ("optically sized") display face with lots of fine detail would complement the strong personality and sparkle of Neutraface text.

House has shown their own Paperback in use with Neutraface.

Hi..context is a wedding invitation. I don't want to set ALL the text in Neutraface..just the RSVPs and the couple's names. The rest can be in another face...preferably serif - still have the programme to do and I don't envision the service notes in Neutraface!

Thanks for the suggestions..will look at them. At the moment I've used Mrs Eaves...for lack of something better.

Ah wedding invitations. Ok. Well maybe Paperback doesn't reflect the style or intent. Are you shooting for something mid-century mod or what?

My yearbook this year will be using neutra face as the headline font and officina as the copy font.

I think they pair nicely...