I have enjoyed reading a long succession of tips on this site. Here's another tip that should be obvious, but often isn't.

The revelation came towards the end of a web project for a medium-sized business. We needed to contact several regular company employees who were temporarily visiting other business locations, but no-one present had mobile telephone numbers for any of them. The obvious thing was to look up the contact details for the locations they were visiting, on the company website.

It was a huge surprise to find the first two numbers failed to connect (either due to typos in the published number, or the published number now being out of service), and the third was answered by someone from a completely different department. What should have been a two minute job ended up taking a lot longer; ringing various other numbers and asking if anyone had the correct details for the intended locations.

If you have physical 'bricks and mortar' locations, and especially if you do business where customers ring you up for sales inquiries and/or to place an order, do make sure that every telephone number on your website is correct and is formatted to be usable and understandable. Customers have a short attention span and plenty of other places to spend their money. Don't present them with incorrect or confusing data.

Mini Survey

A regular audit should be made of all data. Not many sites seem to do this, at least not on a regular basis. A quick survey of various websites for leading UK retailers reveals the following... 

This is not a scientific survey, just a few sites picked at random. Nonetheless, this appears to be damning evidence of the care and attention (not being) given to this easy task. Depending on the site checked, between 2% and 21% of the telephone numbers will fail to connect when dialled as presented.

Lost Opportunities

It's a simple scenario; you have the customer on your site and they're ready to buy. When they pick up the phone to order, they can't get through on the number you have told them to ring. It's an easy job for a customer to abandon your site and buy from some other.

Errors seem to fall into two categories. The first comprise simple typos, where digits are accidentally missed out, added, or transposed, or the wrong digit was typed. These are usually local failures at the point of data entry, and are mostly down to poor typing and failure to check what was entered.

The other types of error are systematic failures within the organisation, mostly caused by failing to notify the web team of store openings, closures, and moves, and of telephone number changes for operational reasons.

Both types of error need to be addressed and re-checked on a regular basis - even going as far as physically picking up the phone and calling every number in turn if necessary.

Directories and Aggregators

The above 'mini survey' looked only at retailers own sites. When the net is cast wider to include data held on business directory sites, the situation is far worse. In among the countless outdated directory entries, there are several major companies that are still listing old London 0171 and 0181 numbers that were scrapped in 2000. Some even list old London 071 and 081 numbers that were scrapped in 1995. Many also have similar errors for their other outlets all around the country. This is a systematic failure on the part of the directory, and is something that business owners have to be proactive in fixing.

There are also several retailers who have these types of errors on their own sites. In those cases, to not have thoroughly checked every entry in their own list in a whole decade is negligence on a grand scale.

Fix It!

Even for fairly major retailers it would only take a matter of hours to manually check their own number list and find all the incorrect entries. Simply pick up the phone and call each number in turn. Tick it off when answered and confirmed as active. That's the easy part; it might take a little longer to gather the right replacement data for those numbers that no longer seem to work. If data is missing, it can often be gleaned from the people working in other branches in the same or in nearby towns, and is soon verified and added to the list. Ideally, there should be someone within the organisation continually collating this data and ensuring wide distribution.

Data held on other sites will take a lot longer to fix. Most of those sites will require registration, and a small number might need a payment. It is important to locally hold copies of all old internal number lists and conduct searches for those numbers to find where they are still published.

Digging deep, I found more than a thousand sites showing incorrect and out of date data about this one particular business. Several hundred errors were easily fixed by registering and editing, or by submitting a 'feedback' form. Several hundred more took a while longer as the 'changes' had to go through moderation by the owners of those other sites, or were dealt with by email to the webmaster. The rest were deemed unfixable as there was no way to directly edit the site data or contact the site owner. Many were anonymous directories with no 'update' mechanism, or anonymous blogs with no 'comment' facilities; and some were obvious scrapers.

A Note About Number Formatting

If you're writing your telephone number for an international audience, ITU-T standard E.123 [ http://www.itu.int/rec/T-REC-E.123/en ](PDF) says to include ONLY the digits that overseas callers MUST dial, and to OMIT all punctuation from within the number [ http://revk.www.me.uk/2009/09/it-is-not-44-0207-123-4567.html ]. Do clearly space out the country code, area code, and local number parts.

That is, do write +44 20 7890 7890, and do NOT write +44 (0) 20 7890 7890. Including the (0) is incorrect.

Use the + symbol to denote the International Access Code, as it differs depending on where the caller is calling from. Most mobile phones will allow you to type the + symbol and the phone network will then automatically sort out the international connection.

Do write +44 20 7890 7890, and do NOT write 011 44 20 7890 7890, because other users may have to use 00 44 20 7890 7890 or something else.

Do write +1 303 890 7890, and do NOT write 00 1 303 789 7890 because other callers may have to use 0015 1 303 890 7890 or something else.

National Numbers

If you're writing your telephone number for a domestic audience, E.123 says to include parentheses around the area code only if that area code may be optional for some callers.

London, UK needs (020) 7890 7890 and California needs (415) 789 7890. This correctly signifies the area code does not need to be dialed when calling from within the same local area.

Now that 10 digit mandatory dialing is in operation in Pennsylvania, you need to write 610 789 7890 without parentheses. To make it obvious the number is located in the US, writing 1 610 789 7890 or +1 610 789 7890 might be even more clear.

Likewise for UK mobile numbers and for 03xx and 08xx customer service and 'call-centre' numbers the code is not optional, so 07700 900555 and 0300 555 7890 and 0845 789 7890 are the correct formats to use.

Final Note

While this isn't exactly an 'SEO' tip, it is certainly another important factor in the running of many businesses. It's hard to measure the effect, but failure to fix it will surely lose sales opportunities.