How to write a business proposal letter (5 Samples)

As someone who has been writing business proposals for over 10 years, I’ve learned that a well-crafted business proposal letter can make or break a deal. Hailing from California, I’ve had the chance to work with various clients—tech startups, small businesses, and even large corporations—each requiring a unique touch. Whether you're aiming to land a new client, pitch marketing services, or request sponsorship, the structure of your proposal letter matters.

Strengthen Your Profile

Before we dive into how to craft a business proposal letter, it’s important to remember that your profile is part of your first impression. Over the years, I’ve noticed that clients respond well when they see a well-rounded individual, not just a service provider. For example, I once worked with a client who later told me they chose me over the competition because my experience and personality came through in my letter.

Think of your LinkedIn, website, or portfolio as an extension of your letter. If the recipient of your proposal letter looks you up, you want them to see consistency and professionalism across the board. If you haven’t already, spend some time crafting your online presence.

What Are Your Desired Job Types?

This might seem obvious, but having clarity about what type of work you want will shape your proposal. Early in my career, I made the mistake of being too broad in my proposals—offering everything from copywriting to website design, which confused potential clients. These days, I focus solely on writing and refining business proposals and marketing pitches. So when you’re preparing your letter, be specific. A targeted message will resonate more than a general one.

What Is a Business Proposal Letter?

A business proposal letter is a document sent to a prospective client or partner, introducing your services or requesting an opportunity. It differs from a full proposal, which often includes detailed project plans, timelines, and pricing. Instead, a business proposal letter serves as a concise, persuasive introduction.

I learned early on that brevity is key. A short, impactful letter is more likely to be read and acted upon than a lengthy one. I once sent a client a full 20-page proposal when all they wanted was a brief introduction—and let’s just say I learned my lesson! Now, I use these letters to spark interest, leaving the detailed information for later.

Further readings: How to write a construction proposal

How to write a proposal executive summary

How to write a technical proposal

How To Write a Business Proposal Letter

Here’s the structure I follow, honed over years of trial and error.

1. Create a Business Header

The header should include your company name, logo (if applicable), and contact details. In a digital-first world, this might seem unnecessary, but trust me—it adds a layer of professionalism. Think of it as your brand’s first impression.

2. Address the Recipient Properly

Personalization is everything. I’ve found that addressing the recipient by name makes a big difference. It shows that you’ve done your research and you’re not just sending out mass letters. There was a time I addressed a letter to “Dear Sir/Madam,” only to find out later the CEO hated impersonal emails. Lesson learned.

3. Include Relevant Background Details

In the introduction, briefly state who you are and why you’re writing. Make sure to mention anything relevant to the recipient. For example, if you’ve worked with similar clients or in a similar industry, mention that here. Once, I opened a letter with a mention of a mutual connection, which immediately helped build rapport with the potential client.

4. State the Purpose of the Proposal

This is where you get to the point. Be clear about what you’re offering or requesting. Avoid jargon or overly complex language. One time, I sent a proposal filled with industry-specific terms, only to find out that the recipient didn’t understand half of it. Now, I aim for clarity and simplicity.

5. Include a Request to Follow Up

Make it easy for them to take the next step. I always include a line asking for a follow-up meeting or call. The trick is to be assertive but polite. Something like, "I’d love to discuss this further at your convenience," works well.

6. Close the Letter Appropriately

End with a professional sign-off. “Sincerely,” or “Best regards,” followed by your full name and contact information is usually sufficient. I’ve found that keeping it professional, yet warm, strikes the right tone.

7. Include Supporting Documentation

If you have brochures, case studies, or any other supporting documents, mention them in your letter. However, don’t overload the recipient. A few key pieces will do.

Business Proposal Letter Template

Here’s a simple template to get you started:

[Your Name]

[Your Company Name]

[Your Address]

[City, State, Zip Code]

[Email Address]

[Phone Number]

[Date]

[Recipient Name]

[Recipient's Company Name]

[Address]

[City, State, Zip Code]

Dear [Recipient's Name],

I hope this message finds you well. My name is [Your Name], and I am the founder of [Your Company Name]. We specialize in [briefly mention your services and how they can benefit the recipient]. Given your expertise in [mention something specific about their company], I believe our [product/service] could provide value to your team.

I would love the opportunity to discuss how we can collaborate further. Could we schedule a meeting at your earliest convenience?

Thank you for considering this proposal. I look forward to hearing from you.

Best regards,

[Your Name]

[Your Title]

[Your Contact Information]

Business Proposal Sample Letter for Marketing Services

[Your Name]

[Your Company Name]

Dear [Client's Name],

I’m reaching out to you because I believe [Client's Company] could benefit from our targeted marketing services. My company, [Your Company Name], specializes in helping businesses like yours increase their online visibility and drive customer engagement. Over the past year, we’ve worked with several companies in your industry and helped them achieve remarkable results.

If you're interested, I’d be happy to discuss this further at your convenience. I’ve attached a brief case study of a similar project we completed.

Looking forward to your thoughts.

Best regards,

[Your Name]

[Your Company Name]

Business Proposal Sample Letter for Sponsorship

[Your Name]

[Your Company Name]

Dear [Sponsor’s Name],

I am writing to inquire about the possibility of [Company Name] sponsoring our upcoming event, [Event Name]. This event will gather industry leaders and influencers, providing a unique opportunity for brand visibility and engagement.

We believe your brand aligns perfectly with our audience, and we’d love the opportunity to partner with you. We’ve outlined several sponsorship levels, and I’d be happy to provide more details at your request.

Thank you for considering our proposal.

Sincerely,

[Your Name]

[Your Contact Information]

Sponsorship Letter Template

Here’s a quick sponsorship letter template you can tweak:

Dear [Sponsor’s Name],

We are excited to invite [Company Name] to become a sponsor for our upcoming event, [Event Name]. This is a great opportunity to showcase your brand to [target audience].

Please let us know if you’d like more information. We’d love to work with you on this initiative.

Best regards,

[Your Name]

Writing business proposal letters takes practice, but once you’ve got the hang of it, you’ll find they’re a powerful tool for building connections and growing your business.

Read my blog on top proposify alternatives