I agree with say170 - do a bit of research into what sat navs cause the issue, and then contact them - however looking on Google maps / some online latitude, longitude tools may help to find and get coordinates from Google maps.
You are able to convert lat, long coordinates from OS grid references - this may be producing the inaccuracy.
Most sav nav companies buy their data in the UK from the Government.
Chances are they probably use the PAF (Postcode address file) from Royal Mail as its the only official source of postcodes in the UK.
This is updated, and maintained by Royal Mail and is updated daily.
How often the companies decide to update the data however is another thing, I heard some update monthly (with RM's monthly updates), whilst others update once a year.
We are having the same problem with our church address. our church is 7300 N. Via Paseo del Sur Scottsdale and people's Gps is is sending them to a someones house. Yes, I would Like to know how to fix this. On some cell phones GPS the people can get there, however on other cell phones or devices people get lost. Please can some one help.
Yes i will do this however this site and the other GPS has the church listed at the wrong address .. the church address is 7300 N. Via Paseo Del Sur in Scottsdale .. and The GPS site on the map that I looked up on this site has the church at 7360 N. Via Paseo el Sur in Scottsdale .. this is why Im trying to fix it .. because people are getting lost the church name is Churchplace...