NAP (Name, Address, Phone)
NAP stands for Name, Address and Phone number, the three business details that must match exactly everywhere they appear online. Inconsistent NAP data confuses search engines about which business is which, and that confusion directly suppresses your local search rankings.
Why it matters for your rankings
Google builds confidence in a local business by corroboration. Dozens of independent sources agreeing on the same details is evidence you are real and located where you claim.
Inconsistency undermines that quietly. An old suite number on one directory, a former phone number on another, and a slightly different legal name on a third are each individually trivial and collectively enough to weaken the signal. The problem compounds because data aggregators copy from each other, so a single wrong record can propagate across dozens of sites for years. NAP cleanup is tedious and unglamorous, which is precisely why so many competitors never do it and why it remains a cheap advantage.
How to check it on your site
Write one canonical version
Fix a single exact format including abbreviations, punctuation and suite notation, then treat any deviation from it as an error to correct.
Search for old data
Google your previous address and phone number in quotes to find stale listings still contradicting the current record.
Add LocalBusiness schema
Mark up your NAP on the site so search engines read it unambiguously rather than parsing it from the footer.
Recheck quarterly
Aggregators reintroduce old data periodically, so a one-off cleanup does not stay clean.