Most NSNP streams ask for proof that you know English or French, usually through tests like IELTS (General Training) or CELPIP. Some employer-driven streams, like the Skilled Worker Stream, might accept different proof of language skills if it's needed for the job and the employer is on board. If you're going through Express Entry-linked streams, you definitely need a valid language test result. So, even though it's not always a must in non-Express Entry streams, IELTS is still the most common and suggested choice.