A Marketer’s Field Guide to B2B Inboxes

Sending email to corporate mailboxes has some unique challenges. You can have the best sending reputation in the world with consumer ISPs but find your email bulked or blocked by numerous corporate filters. The reason for this is that many businesses implement and administer their own email infrastructure and customize it based on their specific needs. These IT staffs have a plethora of hardware and software filtering options at their disposal and can configure them to their heart’s content. It can be very challenging to predict how your email will be handled from one business to another – even if they are using the same message filters.

Know your audience. We find that many companies say they are sending B2B email when in fact a large population of their subscribers are using mailboxes at the major consumer ISPs with addresses like @hotmail.com, @yahoo.com, @aol.com and the like. Deliverability best practices at these providers are much different than corporate email systems. To help guide your approach to improving inbox placement rates, we suggest that you first run a domain report on your list file to understand the percentage of consumer ISP domains versus true business domains.

Small and medium-sized businesses. More and more small and medium sized businesses are using hosted email solutions to manage their email. In these cases, there is a little more deliverability predictability (say that five times fast!) due to fewer customization options. Providers in this space include Rackspace, Amazon, Google Apps, GoDaddy and Tucows to name a few.

Large enterprise businesses. Large enterprises with big IT budgets have a broad range of email filtering options at their disposal. Here are some examples of the layers they may implement:

• Gateway filters and appliances include Barracuda, Cisco IronPort and Trend Micro InterScan. Some email administrators will create their own custom filters at this level to add additional security measures for their network.
• Hosted filtering in the cloud includes Symantec MessageLabs, Google Postini and Websense.
• Software solutions include anti-virus (Sophos, Kaspersky) and anti-spam (Symantec, IronPort, Barracuda, SpamAssassin, Proofpoint).
• End-users also have the ability to define their own filtering rules at the client level with applications like Outlook and Thunderbird.

Manage your content. Different industries utilize varying levels of filtering depending on their security goals. Financial, insurance and healthcare businesses are very restrictive of the type of email they allow their users to receive. Emails with attachments, heavy images and lots of links will receive more scrutiny in these verticals and may be blocked or dropped all together. Financial businesses are prime targets for phishers so their security teams take extreme precautions to keep phishing emails, malware and viruses out of their environments.

In general, there is also less tolerance for email with spammy words, social and sexual content and other messages that might be more acceptable in a B2C environment. If you are a Return Path client, leverage the B2B seed list in Mailbox Monitor and run the Spam Filter Check and Content Assessments in Campaign Preview to improve your inbox placement rates.

List acquisition and maintenance. Every touch point with a business contact is an opportunity to collect email addresses organically. Even so, many businesses still choose to rent or purchase addresses and perform email appends on their list files which can cause havoc on deliverability if not done correctly. It’s also common practice for some businesses to guess at a customer’s email address by mailing to [email protected], [email protected] and [email protected] hoping that they’ll reach John Smith at Acme Company. In addition to the deliverability issues this will create, this practice goes against best practice permission-based email. Furthermore, businesses may choose to report you to their Anti-spam vendor and/or blacklist (block) all mail from your domain/IP if they feel you are avoiding best practices.

Encourage your subscribers to whitelist your domain to help bypass filters and get your email delivered with images on and links enabled.

Sending infrastructure. Implementing DKIM and SPF authentication is still a best practice for B2B mailers. Remove hard bounces from your list immediately. If you are utilizing a CRM system such as Salesforce or a marketing system such as Eloqua, you should know whether you are sending from dedicated or shared IPs. If using shared IPs, ask your vendor what the reputation, authentication and infrastructure configuration is to maximize deliverability results.

Keeping IPs warm and maintaining a consistent sending reputation can be problematic for some B2B senders who send email infrequently – such as once per quarter or semi-annually. If you experience deliverability issues you may want to consider adding another mail stream to this IP or sending out “heartbeat” emails to maintain more sending history with receivers. Infrequent mailings can also lead to spikes in unknown user rates which can adversely affect your reputation. Be aware of these issues and plan ahead.

Email laws. Some businesses think that email and privacy laws such as CAN-SPAM, Canadian Anti-Spam Legislation and European privacy laws only apply to B2C email. Businesses are held to the same laws and standards as B2C mailers. Be sure to include an unsubscribe option and your company address or other required information in your messages as defined by these laws.

Did you miss a post from our Email Marketer’s Field Guide series? Catch up now:

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