Linguistic register is defined as a variety of language shaped by different situational settings. Adapting to register is globally crucial for successful communication, and doing so efficiently involves the processing of language features related to register variation. Despite its central role in communication, few studies have focused on the impact of linguistic register on the way we process language. Our research fills this gap by investigating whether register variation affects the ability to detect linguistic errors, due to different degrees of anticipation of such errors in high vs. low registers. To determine if linguistic background further impacts the way we deal with register, our sample includes different groups of majority language monolingual and bilingual participants as well as minority language bidialectal participants. All groups completed an acceptability judgement task that features Subject-Verb agreement mismatches presented in both high and low register. The results reveal a significant impact of linguistic register on accuracy: Morphosyntactic errors are better detected when stimuli are presented in low register. Furthermore, different trends characterize the tested groups. While monolinguals show similar accuracy rates for low- and high-register sentences, the bilingual groups tend to better spot errors in the low-register stimuli. Our findings suggest that register plays an important role in the processing of morphosyntactic errors, highlighting the need to consider both its cognitive and social dimensions. Moreover, the variation observed among the tested groups underscores that language processing can be influenced by factors related to the sociolinguistic dimensions of each linguistic community.