As far as I am aware, unlike APA style, Chicago style does not demand a different for citations inside and outside of a pair of parentheses. This distinction is something characteristic of APA style.
So the 'equivalent' of biblatex-apa
's \nptextcite
for biblatex-chicago
is probably just \cite
: That will give you a citation without parentheses.
\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{babel}
\usepackage{csquotes}
\usepackage[authordate, backend=biber]{biblatex-chicago}
\addbibresource{biblatex-examples.bib}
\begin{document}
(see \cite{sigfridsson} for an introduction)
\printbibliography
\end{document}

If you are already heavily using \nptextcite
in your paper and don't want to switch the command in case you go back to biblatex-apa
, you can add
\newcommand*{\nptextcite}{\cite}
\newcommand*{\nptextcites}{\cites}
to your preamble.
\nptextcite
necessary in the first place), so you could probably just use\cite
.