If you're still on the fence about sending holiday cards to your clients, here's a list of seven reasons why you should absolutely go for it every year.

1. A holiday card is more meaningful than a holiday email

Have you ever received an email that left you feeling valued the same way a handwritten card from a family member did? Probably not. That’s because a handwritten card is a much more personal. You know your Nana put a lot of time finding the right card, writing a nice note, including a gift card and dropping it in the mail for you.

Let someone else clog up your clients' inboxes with holiday emails while you do something special and personal like a handwritten card. Your clients will notice.

2. Cards help you reach out to clients you haven’t spoken to recently

Even with a solid communication strategy, some clients fall through the cracks and may not hear from you as often as they should throughout the year. They might miss an email or opt not to respond to a survey.

A handwritten card delivered straight to their mailbox creates a positive experience, instantly puts you top of mind and reminds your clients you care even if you haven’t spoken to them in a while. This alone is usually enough to encourage your clients to fill out the next survey. And as you know, more responses lead to more promoters and referrals.

3. Cards build goodwill

Holiday cards are a great way to build goodwill that an email simply doesn’t have the power to do. Think of goodwill as currency—every time you provide your customers with a great experience like a handwritten card—you are adding to their piggybank of goodwill.

4. It’s about the relationship, not insurance

When your clients get an email from you, it's often related to their policies or insurance in some way.

A holiday card is a simple gesture that takes the focus away from business and puts it on the relationship. It shows your customers you genuinely care and you don't want anything in return.

5. People open, keep and share handwritten cards

Sending a holiday email is a quick way to do what all other companies, including your competitors, are doing during the holiday season. Just think of your own inbox, it's full of sales, offers and holiday wishes. Consumers are overwhelmed, and most of these emails get ignored.

Holiday cards are different. Many people display cards on their fridge or mantle, or even hang them on their tree like ornaments. This creates the perfect opportunity for natural word-of-mouth referrals without you having to do anything else.

6. Cards have a big impact on client retention

We found that 81% of clients who leave an agency do so due to lack of regular and meaningful communication. Holiday cards are a great way to retain these clients and show you care about them outside of renewal times.

Your clients know a holiday card is optional, and since you aren’t asking them for anything in return, they will feel valued and less likely to leave.

7. The ROI speaks for itself

Sending out holiday cards isn't cheap, until you realize the impact it has on retention and referrals.

We've done the math. You only need 1 out of 125 cards to inspire a client to stay another year (or to refer someone else) for you to break even. Sending your clients handwritten cards also increases your Net Promoter Score (NPS) by an average of 8 points over a 1-year period—increasing overall agency retention by about 2 percent.