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How to Write a Cover Letter for an Unsolicited Sales Proposal

by David L. Seibert

You should always include a cover letter when you send a proposal. Itís good business etiquette, itís polite, and thereís no reason not to.

With this said, though, donít go overboard. One of the mistakes that many proposal writers have made, me included, is to try and summarize the proposal in the letter. The problem with this is that Iíve already summarized the proposal in the executive summary. Why do it again?

Purpose of a cover letter

The purpose of the cover letter is to introduce the proposal. It accompanies the proposal when you deliver it to the customer, but it isnít part of the proposal. In fact, the proposal and the cover letter have two different audiences. A proposal is from you to all the people in the customerís organization who are involved in making the purchase decision. The cover letter, in contrast, is between you and the person who has been your main contact. The only exception to this rule is if you are writing a proposal in response to an RFP, and the RFP specifically instructs you with something like this: "you should include a letter that says this..." In these cases, follow their instructions instead of my advice.  

In general, though, the cover letter should be a personal note between you and the other person with whom youíve been working. Certainly, there is a lot more you could put into it if you want to, but resist the temptation. Youíll gain nothing by it. In fact, you probably do little more than increase the length, and that will do little more than increase the likelihood that it wonít be read.

In general, there are two types of cover letters that you could write; one that is complimentary and personal, and the other that is more formal but still personal.

Cover letter type 1: complementary and personal

Wherever possible, write your cover letter so it is complimentary and personal. In this type of letter, I thank the person Iíve been working with for the time he or she has taken with me. If sheís been very helpful, I make a special point to tell her how helpful sheís been. If he has helped to improve the solution Iím proposing, I go out of my way to tell him how heís benefited his organization.

Dear Debbie:

Enclosed is the proposal I promised you, titled: Improving Office Productivity by Using Fast, Dependable Copiers.

I also want to take this opportunity to thank you for all your help. Designing a suitable solution for ACME Coffee Cups required that I become familiar with your products and your industry. Since I didnít have much background in your industry, this represented a challenge. As a result, your help and guidance proved to be invaluable. Indeed, because of your tutelage, I was able to build a solution from a position of knowledge. Ultimately, this resulted in a better, more cost effective solution for your organization.

I will call you next week to discuss this proposal. As always, please donít hesitate to call me if you have questions or if I can be of further assistance.

I hope we can continue working together into the future.

Sam Seller

I send a cover letter like this for two reasons. First, I send it because itís the right thing to do. We donít spend enough time in this world thanking peopleósincerelyófor what they do. Second, I send a personal note like this because it is more persuasive than the typical, boring cover letter that says, ďhereís my proposal, please read it.Ē

Research shows that if you compliment someone, then they feel compelled to return the compliment. If you do a favor for them, then they feel compelled to return the favor. The research is clear, unambiguous, and irrefutable; do something nice, and people feel compelled to do something nice in return.

Sometimes, the favor you get in return is comparable to the favor you gave, but sometimes, it is much more. Say, for example, I send you a jam, jelly, and cheese basket at the holidays. You immediately think about what a nice thing that it was for me to do, and admit it or not, you want to do something nice in return. You may not send me a gift basket, and you probably wonít award me the contract if Iím not qualified or if my price is too high. However, if I'm qualified, and my bid is among the leading contenders, who are you going to argue should win the business? Your old buddy that keeps you stocked in jam, jelly, and cheese, thatís who.

Right now, there are two groups of people reading this who are having strikingly different reactions; those who are offended at the idea of giving a compliment to receive a favor, and those who see an opportunity. The first group is thinking that this sounds like a really seedy way to persuade people. The opportunistic group is thinking, ďif this is so effective, why donít I just stop advertising and send out gift baskets to everyone, instead?Ē Both groups are missing the point.

In regards to this being a seedy approach, nothing could be further from the truth. We teach our kids that they can catch more flies with honey than with vinegar, donít we?  Basically, weíre just teaching them to be nice to other people. Weíre teaching them that if someone does something nice for them, that they should say thank you. This is no different. I am not advocating that you make up a fake compliment or thank someone for something that he or she really didnít do, only that you acknowledge someone elseís efforts.

In regards to the opportunistic groupódonít fire your advertising agency just yet. This principleóformally referred to as reciprocationóhas already been beaten to death by advertisers and non-profits. One of the greatest examples is when you get address labels, typically around the holidays, from a non-profit organization. Thereís no obligation to pay for the address labels, of course, itís just a gift. In reality though, an obligation is created, if only in the mind of the recipient. The recipient of such a gift feels obligated to return the favor, and more often than not, will send a check. 

Understand this: within business to business selling, reciprocation generally only works within the context of an established relationship in which the recipient is open to the gesture. So before you try to use this approach to your advantage, you have to take two tests; the morality test and the reality test.  

 Morality test

On my first professional sales job, I was given a couple sales brochures and a telephone, and was told to sit down and start dialing. Amazingly, it didnít take long until I got hold of a guy who was interested in what I was selling. Almost predictably, given my minimal level of training, he asked a question to which I didnít know the answer, so I put him on hold and ran to the next office to ask a more senior associate.

ďIíve got this guy on the phone and heís interested in this product, but he wants to know thisÖĒ, and I spelled out the guyís question.

My associate never faltered: ďTell him yes, it does that.Ē

ďIt does?Ē I replied, kind of surprised.

ďI donít knowĒ, came the quick response, ďbut weíll find out later.Ē

My first business to business sales job, almost my first day, and here was a senior sales rep advocating that I lie. It was a dilemma. I wanted to fit in, to be a team player, but I didnít want to lie. Ultimately, the course of action was clear to me. I told the customer I didnít have an answer but I would find out. I ended up calling him back later after I knew the facts.

Iíve always remembered this one incident because itís become a moral compass for me. It wasnít a huge issue with big implications. I could have lied and kept the conversation going. Then if I found out later that I was wrong, I could have called him back and admitted I was wrong. No great damage done, right? Not to that customer, perhaps, but certainly to my integrity.

The point is this; when it comes to issues of right and wrong, the big issues are easy to handle because theyíre so clear. Itís the small ones where weíre tested.

So getting back to the cover letter discussion, it is a good thing to say something nice to someone who deserves itóand get the benefit of reciprocation. However, only you can decide whether to compliment someone for something they didnít do, or didnít do well, just so you can send a complimentary letter that earns you extra favor. Personally, I think it amounts to lying.

Reality test

Have you ever gotten a greeting card or birthday card or something else from someone you donít particularly like or care to be around? Donít you hate it? You hate it because now you feel compelled to at least acknowledge the gesture. You might even feel compelled to return the favor. If itís someone you like, thatís one thing. But if itís someone you donít particularly care for, itís a bummer.

Speaking of jam, jelly, and cheese baskets, I was once getting ready to fire a firm that was doing work for us. It was around the holidays. The very day I was going to call the president of the firm to tell him of the change, I received a jam, jelly, and cheese basketóvia courierófrom the president, himself. What incredible timing! Now if I call him to fire them, I feel like a jerk. The basket worked, sure enough; it kept me from firing them for a month. But it inspired ill will, too. Indeed, it made me angry because now I felt like I had to wait a little while before I could fire them. I know, I knowóI shouldnít have let that influence what I was going to do. But hey, Iím human, too, and like most humans, stuff like this does affect me. It didnít change my decision, it just slowed it down.

Now turn it around. If you send a complimentary cover letter to someone who youíve worked with, built a relationship with, and who deserves it, the sentiment you express will probably be well received. However, if you send a complimentary cover letter to someone who hasnít been particularly helpful or who doesnít deserve it, whatís going to happen? Theyíll raise their eyebrows and then scowl with skepticism as they read then reread your letter. Ultimately, theyíll dismiss it offhandedly saying, ďI wonder what he wants?Ē It wonít have the desired effect.

Thatís the reality test. If youíre working with a customer, and you canít pass both the morality and reality test, then forget letter type one and move on to letter type two.

Cover letter type 2: Formal but still personal

In general, I believe strongly that a complimentary letter is better than a canned, boring cover letter. But for all the reasons discussed in the previous section, sometimes you shouldnít send a complimentary note. Sometimes, it makes much more sense to send a letter that is more formal. Itís still a personal note between two people, itís just more formal than the previously described complimentary letter.

 Dear Ms. Buyer:

 I enjoyed speaking with you about your proposal project. 

Attached is a sales proposal that describes our writing service called the Sales Proposal Quick Start Package. The Sales Proposal Quick Start Package is well suited to organizations, like ACME Coffee Cups, who want a well-written and persuasive sales proposal at a reasonable price. It is also ideal for organizations who want to develop their own sales proposal, but need a well-written, well-structured sales proposal as a place to start.

I look forward to working with you on this worthwhile project. I will contact you in a couple days to answer any questions you may have. In the meantime, please do not hesitate to call me if I can be of further assistance. I can be reached at 123-456-7890.

Sam Seller

This letter serves the purpose well. Itís long enough to accomplish your goal; introducing your proposal. But itís short enough that it will be read. Sure, it isnít as fancy or influential as the previous letter, but it is entirely appropriate for the circumstances. 

The bottom line is this; you should include a cover letter whenever you send a proposal, but don't over think it. Keep it personal--between you and the person you're sending it to--and appropriate for your relationship. This increases the effectiveness of your letter. It also saves you a lot of time that you can spend writing your proposal.

David Seibert is a professional salesperson, proposal writer, and proposal consultant. He is also the founder and president of The Seibert Group, a proposal consulting and training organization serving businesses that sell to other businesses and to state and local governments. You can contact him at