Information provided by 411 is not always up to date, as of 2015. The information can be either current, up to three days old, entirely dated or non-existent, depending on its source.
A 411 service provided by a local carrier has current phone listing records for its own clients. If using 411 to track a number managed by a non-local carrier, data is commonly aggregated every 72 hours, if it is shared at all by the particular carrier. However, numbers may not be listed if they reside outside of someone's own phone service provider. Because of local exchange competition, 411 data is no longer comprehensive if coming from a single regional provider's subscriber roll.
In response, many carriers have outsourced their 411 service to specialized call centers which maintain more complete records collated from various carriers. However, phone service providers are not obligated to share their clients' information with these 411 directory services and often do not.