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How to Write a Business Proposal Letter

Written by:

Victoria Yu is a Business Writer with expertise in Business Organization, Marketing, and Sales, holding a Bachelor’s Degree in Business Administration from the University of California, Irvine’s Paul Merage School of Business.

Edited by:

Sallie, holding a Ph.D. from Walden University, is an experienced writing coach and editor with a background in marketing. She has served roles in corporate communications and taught at institutions like the University of Florida.

How to Write a Business Proposal Letter

How to Write a Business Proposal Letter

When you want something in life, you should just go get it! That’s what we’ve been taught by pop culture, but in the business world, charisma and boldness can only take you so far.

If you’re running a B2B business and looking for potential partners and clients, at some point you’ll likely need to draft a formal deal proposal. In the business world, it’s crucial that you learn to prepare an effective business proposal letter, as a poorly written proposal letter could result in the loss of a major opportunity. 

Whether writing your first proposal or looking to improve your skills, this guide outlines the keys to crafting an excellent business proposal and proposal letter that will help you lock in great deals. 

What’s a Business Proposal Letter?

A business proposal letter is exactly what it sounds like: a letter sent to prospective clients or business partners laying out the reasons they should do business with you.

Sometimes what’s being proposed is a collaboration, in which case the product you’re selling is yourself. But in most cases you’re explaining to a potential client why your company and its services are the best fit for them and their needs. For B2B firms, a good proposal letter could ensure your business success. 

If Toyota announces they’re going to build monster trucks, for instance, you as a tire company might write a business proposal letter to Toyota explaining why your firm should be the exclusive supplier of tires for their new truck line. 

Difference Between a Business Proposal Letter and a Business Proposal

Sometimes people use the term “business proposal letter” and “business proposal” interchangeably. But in reality, a business proposal letter is an executive summary and cover letter for a full business proposal, which is a multi-page report that extensively details the proposal. 

Although, for smaller proposals, you might only send the business proposal letter. In any case, the proposal letter can be a stand-alone document detailing a proposed business agreement.

This guide aims to provide you with a comprehensive picture on how to write the entire business proposal. By the end, writing the summary proposal letter should be a walk in the park.

How is This Different From a Sales Pitch?

Compared to a sales pitch, a business proposal and proposal letter are much more formal. Rather than just a one-and-done deal, the transaction proposed in the letter usually has a more long-term vision. 

Your might be proposing a project collaboration, an exclusive supplier contract, a years-long order, or something that could reshape you and your target company’s reputation. A business proposal is usually a big deal for both parties and needs approval from top decision-makers before being finalized.

But both require some research on the prospect (potential client) and their needs. However, unlike a normal sales pitch, your business proposal may well be in direct competition with other firms making similar offers. Therefore, if you want that deal, your proposal and letter need to set the gold standard!

Types of Business Proposals

There are three types of business proposals: a formally solicited proposal, an informally solicited proposal, and an unsolicited business proposal.

1. Formally solicited proposals

In a formally solicited proposal, the client company has requested and is likely expecting your proposal. This is usually done on an industry level, with a company putting out an RFP (request for proposal), a call for potential suppliers to send proposals so it can review and choose the best one.

Our Toyota example from earlier is a good example. Toyota might have announced this plan at a big auto event and formally invited all tire companies present to send proposals by a certain date.

2. Informally solicited proposals

An informally solicited proposal is fairly similar to a formally solicited proposal, but with less red tape. After a conversation with the prospect, their rep might personally ask you to send a proposal. 

This usually means that the prospect already has some interest, so your proposal probably doesn’t need to be aggressively sales-y. Instead, you can focus more on the practical details of your offering.

But even if you’re on the fast track, it’s best not to rest easy until the deal is sealed!

3. Unsolicited business proposals

Finally, an unsolicited business proposal is closer to a written sales pitch or marketing brochure. They’re generic advertisements for your company and services that do not target any specific potential client. They’re often handed out like candy at trade shows and industry events in the hope of attracting interest.  

They do sometimes work, but be careful: sending out lots of spammy, unsolicited proposals can damage a firm’s reputation, doing more harm than good.

Before Writing: Research Your Prospect

Writing a whole proposal is a lot of work, and you might be tempted to just write one unsolicited business proposal letter and send it out to everyone, regardless of the situation. Resist that temptation. 

Having one standard business proposal letter will surely save you time, but it will also reduce client interest in your offerings. Customizing each proposal shows potential customers the respect they’re due and increases your chances of securing their business by hitting on their pain points.

Personalizing your pitch takes the analytical stress off of your prospect’s shoulders, making it easier for them to move toward “yes.”

Formally and Informally Solicited Proposals

For formally and informally solicited proposals, take the time to research the company and the challenges it might be facing. Perhaps management recently changed, or the business, or a relevant department, went through a major restructuring. It’s also a good idea to see what the target company’s competitors are up to; maybe the company is about to fall behind, or has a chance to gain a real edge. 

Check the Better Business Bureau, LinkedIn, social media platforms, and the company’s website to get a full sense of the company and its situation. The more you know about the prospect and company, the better you can tailor your value proposition to match their needs.

Unsolicited Proposals

An unsolicited proposal isn’t an excuse to skimp on details either: you can still personalize your offering to fit your ideal customer profile (ICP). As a company, you should already have a good idea of your target audience, their pain points and needs, and how your company could solve them.

Unlike a sales pitch or cold email, your business proposal letter should focus entirely on the client as a company rather than including details about a representative or contact person. Save the “it was nice to meet you” for in-person meetings and email greetings rather than the proposal itself.

Elements of a Business Proposal Letter

So you’ve got your goal and prospective client in mind and you’re ready to start writing. The next step is your title page, which presents some key bits of information. 

Like many formal reports, business proposals and proposal letters have a relatively strict structure to which it’s best to adhere as a sign of professionalism. Also, following the common template ensures you don’t forget any key elements. 

1. Title Page

Your title page should include the title of your proposal, the name and contact info or your business, and the proposal submission date, if there is one. If you’re writing an unsolicited proposal, include the date on which the letter was written. 

Unlike the bland APA-style title pages common in college reports, your business proposal letter’s title page should be appealing, almost like an advertisement. Use fun-yet-tasteful fonts, your brand logo, images, and other elements that fit your brand or allude to the proposal. 

Your title page should be a real attention-grabber. But be sure not to overdo it with too many elements or loud colors. You’re looking to convey an appealing sense of style and professionalism with a few simple elements. 

The fonts and colors you use here set the mood for your proposal, so choose wisely. 

2. Table of Contents

You can put your table of contents before or after the cover letter, but it needs to be one of the first elements in your business proposal. 

Though often overlooked, the table of contents is another place where a little work can go a long way toward ensuring a successful deal. The easier it is for decision-makers to find relevant sections, the faster they’ll make a decision. 

Your readers’ time is precious, and if they have to spend several minutes skimming your full proposal every time they need one piece of information, they’ll likely grow frustrated with the proposal and with your company. 

Simplify this by titling each section clearly and concisely: rather than “Our Tires Are 70% More Durable Than Competitors’,” try “Incredibly Durable Tires.” Also, as a reference page they’ll likely lean on, the table of contents should be full of white space to give readers a mental break.

Under distinct sub-headings, clearly demarcate sections the reader will be most interested in knowing, such as pain points and answers to likely questions.

3. Cover Letter

Next is your cover letter, which begins with a detailed intro of you and your business. Briefly detail the company’s background, why you started the firm and how you developed your mission and vision. 

You might include a photo of yourself to help the prospect put a face to the company. As with the title page, include your contact info. Also, encourage the reader to reach out with any questions. 

End the cover letter with a friendly and polite closing, thanking them for their time. 

4. Executive Summary

Arguably the most important part, your executive summary should concisely answer what your company can do and why you’re the best option for the task.

Just as you would in a sales pitch, describe your proposed solution to the prospect’s pain points, and explain why choosing your company is the best course of action for your potential customer.

The executive summary shouldn’t be too detailed, just 2-4 pages. It should be strong enough to stand on its own but leave out just enough detail to pique readers’ interest, enticing them to read on.

Though it appears near the beginning of the proposal, you probably want to write the executive summary after you’ve finished the business proposal. That way you’ll know exactly what’s in the report, and its main points, before you attempt to summarize it in an enticing way.   

Even if you’re writing a general unsolicited business proposal letter, it should read as if you’re writing to one specific company. This will give you a better chance of developing a personal connection.

5. Value Proposition

The value proposition is where you outline your customer’s problem and your solution in detail. This will likely be the longest section of your business proposal.

In the executive summary, you explained what you can do and why you’re the best. In this section, explain how you’ll do it and when you’ll have it done. This is where you can flex your research muscles and lay out how your company will meet the client’s specific needs.

Give a solid project timeline of when you expect to have key tasks done. Go into detail about how your client will receive progress updates: method of delivery, metrics and KPIs, and so on. Some options for reporting are real-time analytics, monthly reports, or a designated contact person.

As in the table of contents, use clear headers for each problem, solution, goal, or benefit, providing signposts for the flow of your argument that help readers find the sections they need. 

Charts and graphs would also help readers visualize your explanations and prevent reading fatigue. Just avoid anything too loud or decorative. 

Unlike a standard in-person sales pitch or demo, a sales rep isn’t going to be present to answer questions or handle objections. So be sure to spend some time thinking about potential concerns the client might raise, and address them directly in this section. 

Of course, a potential client could always contact you directly, but you’re unlikely to get a deal if your business proposal generates more questions than answers. 

6. Pricing Table

Now that you’ve made your case, all that’s left is negotiating a price. Again, without a sales rep present, haggling will be a bit different. Instead of a single firm asking price, provide an easy-to-read pricing table that offers several options and plenty of wiggle room. 

The more flexible your offer, the easier it is for your prospective client to find an appealing option. Be sure to include any relevant discounts, add-ons, upgrades, and installment or recurring payments.

Your descriptions should be transparent and easy to understand, as any misunderstanding could result in major headaches down the road.

7. About Us

Briefly describe your business, its story, vision and company culture. Your potential customer should by now be assured about your product offering, but they also want assurances about your company. 

If you have an “About Us” page on your company website, you could just condense that down into a few paragraphs for this section. If not, create an authentic and compelling narrative that could help build a personal connection with the client. 

8. Qualifications

What reassurance can you give your prospect that you’ll deliver everything you’ve promised? Explain here why you’re the best-qualified business for the job.

Rather than taking your word for it, most people prefer actual proof! People tend to trust their fellow consumers. If you have case studies, endorsements, and testimonials from previous happy clients, here’s where to put them.

9. Call to Action

Wrap up your business proposal with a strong call to action, asking them to contact you or set up a meeting to discuss details. If you’re especially confident, you could even include a full listing of terms and conditions and a legally-binding contract for the recipient to sign. 

Keep in mind that your proposal itself can’t serve as a contract: it will need some tweaks and adjustments to turn it into a contract fully compliant with the law. After that, both parties must approve and sign. 

Whichever route you choose, just be sure to give a clear picture of the next step toward making a deal.

After Writing: What to Do

So you’ve got your whole business proposal drafted and in hand. Congratulations on your hard work, but there’s still more work to be done. 

Editing, Proofreading, and Formatting

First, since your first draft is likely to be bloated with extra words, get ready to trim down your proposal to make it more presentable and easier to read.

Use clear and concise language and a professional tone. Avoid jargon and technical terms except for in the value proposition section when needed. Proofread your document for typos.

There’s no one font or font size you’re bound to, but keep it professional and on-brand – that means no comic sans! Check other formatting elements such as your margins, line spacing, references, and page numbers to keep your document easy to read. 

Make sure the formatting for your document is consistent. A single mistake might slide, but a business proposal rife with little errors comes off as unprofessional. Rather than landing you at the negotiation table, that business proposal will likely end up in the trash can.

Condense Into A Business Proposal Letter

Assuming you’re sending an entire business proposal, your business proposal letter serves as a cover letter for the entire proposal. Your business proposal letter’s structure should be much like a cold letter or email: build a connection to the recipient, and detail their pain points before highlighting your value proposition. 

End with a clear call to action and friendly closing. In essence, it should be a one-page version of your executive summary and cover letter rolled into one. If you’re sending a physical letter, place your company header at the top of the paper. 

If you’re emailing, put your company name and reference to the proposal in the subject line. Attach your full business proposal to the letter or email, and send it out.


A business proposal letter summarizes the longer, more complex business proposal, but it’s still valuable in highlighting the value you can bring to a prospective client.

With strong business proposals and proposal letters, your company could spark an influx of enthusiastic new clients, putting you on the path to serious sales and success. 

Business Proposal Letter FAQs

Should I Use a Proposal Letter Template?

It’s not a good idea. Of course you can reuse your cover letter and about us sections, but a cut-and-paste proposal letter template runs the risk of making your letter sound robotic and impersonal, which reduces the chance of building a connection and making a sale. 

Personalized proposal letters have a much higher chance of grabbing your potential client’s attention and honing in on their specific needs. If you’re writing a formally solicited business proposal competing with other proposals, a handwritten proposal and letter could stand out among competitors who used a template, or even worse – AI-generated content.

Should I Print Out My Letter or Send It Digitally?

A physical letter might have more impact upon delivery, but an email is just plain convenient: the recipient can forward it to as many people as necessary and there’s no chance of it getting lost.

If you do decide on sending a letter in the mail, it’d be best to follow it up with a digital copy.

What Program Should I Use to Write My Proposal Letter?

Some software and online programs such as PandaDoc and can help you write your proposal letter. But if you’re confident in your writing skills, you could draft the entire proposal and proposal letter in MS Word using the steps outlined above.

How Do I Make My Business Proposal Letter Stand Out?

To make your business proposal letter stand out, tailor it to the needs and expectations of your target client and go above and beyond using clear, concise, and professional language.

Beyond the words, the visual elements of your business proposal also make a lasting impression – the images on your title page, impactful graphs and charts, and an easy-to-read format. The more pleasant your business proposal and letter, the better impression you’ll leave on readers.

Who Do I Address My Business Proposal Letter To?

Your business proposal letter should be addressed to the primary decision-maker or point of contact with a company. 

If a company made a formal request for proposals, they’ll likely have included details on who to send your letter to and how. For informally requested proposals, send them to the person you talked to, with a brief mention in your letter of how and when you talked last.

If you’re cold-emailing unsolicited business proposals, you’ll have to do a bit more digging online into who the most appropriate person to send your letter to would be. Make sure your recipient is both invested in the pain point you address in your value proposition and has the authority to present your offer to the rest of the company, like a top executive.