This is the first lecture in Module 1. No prior lecture is required.
← No prerequisite for this lectureA letter is a written message conveyed from one person or organisation to another through a medium — traditionally paper, and increasingly electronic (Olusegun, 2019, p. 4). Although digital communication has expanded rapidly, the formal letter remains the backbone of professional, legal, and institutional correspondence in business, government, and academia (Bello & Nwosu, 2020, p. 11). Understanding how to write a letter correctly is, therefore, not a historical curiosity — it is a practical necessity.
Letters serve multiple purposes: they record information for future reference, communicate decisions and directives, establish or maintain professional relationships, and provide documentary evidence in legal or organisational disputes (Olusegun, 2019, p. 6). Because a letter is often the first contact between two parties, it creates an immediate impression of the writer's competence, professionalism, and character (Adeyemi, 2021, p. 14).
A letter is an ambassador. Before you write a word, understand that your letter will represent you long after the conversation ends. It may be filed, quoted, or produced as evidence. Write accordingly.
Scholars of business and professional communication have long identified a set of qualities that distinguish an effective letter from a poor one. These are commonly summarised as the Seven C's of Communication, each representing a standard the letter must meet (Bovée & Thill, 2021, p. 28).
Letters are broadly classified into two categories based on the relationship between writer and reader and the purpose of the correspondence (Olusegun, 2019, p. 18).
| Feature | Formal Letter | Informal Letter |
|---|---|---|
| Audience | Organisation, official, authority, or unknown person | Friend, family member, or close acquaintance |
| Tone | Professional, respectful, neutral | Personal, warm, conversational |
| Language | Standard formal English; no contractions or slang | Relaxed; contractions and colloquialisms acceptable |
| Structure | Rigid — all standard components required | Flexible — only greeting and closing obligatory |
| Salutation | Dear Sir / Dear Madam / Dear Mr. Okafor | Dear John / Hi Ngozi / My dear friend |
| Complimentary Close | Yours faithfully / Yours sincerely | With love / Best wishes / Yours ever |
| Examples | Job application, official complaint, business proposal | Letter to a friend, letter to a relative abroad |
Critical rule: Use Yours faithfully when you do not know the recipient's name (i.e., when the salutation is Dear Sir or Dear Madam). Use Yours sincerely when you have used the recipient's name (e.g., Dear Mr. Okon). Mixing these is one of the most common errors in formal correspondence.
Beyond the Seven C's, professional communication scholars identify a set of practical principles that guide the drafting process itself (Adeyemi, 2021, p. 31). These principles govern not only what is said, but how, when, and with what awareness of the reader.
Before writing a single word, the writer must clearly define what the letter is meant to achieve. Is it to inform, request, persuade, acknowledge, apologise, or complain? A letter without a clear purpose rambles, confuses, and fails (Bovée & Thill, 2021, p. 33). Write the purpose in a single sentence before you begin; that sentence will govern the entire letter.
The register, tone, and vocabulary of a letter must be calibrated to the reader's position, background, and expectations (Bello & Nwosu, 2020, p. 27). A letter to a Managing Director reads differently from one to a departmental colleague, even when both concern the same subject. The reader's level of technical knowledge, their likely emotional response, and the nature of your relationship with them must all shape your language choices.
Effective letters are not written in a single spontaneous flow. Professional writers outline their key points before drafting: they decide on the main message, the supporting details, and the sequence of paragraphs (Olusegun, 2019, p. 22). An unplanned letter invariably produces disorganised paragraphs, missing information, and the need for a follow-up.
Language in a letter must match the context. Formal letters require standard, dignified English free of contractions (cannot, not can't), slang, and colloquialisms. Informal letters permit a warmer, more personal register. In both cases, language should be natural — not artificially inflated or unnecessarily complex (Adeyemi, 2021, p. 37).
A well-structured letter moves the reader from context to content to conclusion without confusion. The conventional structure is:
No letter should be sent in its first draft. Revision checks structure and logic; proofreading checks grammar, spelling, punctuation, and formatting (Bovée & Thill, 2021, p. 44). A common professional practice is to set the draft aside briefly before re-reading it — errors that were invisible in the heat of writing become obvious when the mind has rested.
Figure 1: The nine components of a formal letter illustrated through a sample job application. Each numbered element is mandatory in formal correspondence. Adapted from Olusegun (2019, p. 30) and Adeyemi (2021, p. 44).
Each item below shows a sentence or situation taken from a real letter. Identify which of the Seven C's or the Six Principles is violated, and state how you would correct it.
The seven letters that follow are fully worked samples representing the most common categories of professional correspondence. Study the structure, tone, language, and layout of each. Notice how the principles of the Seven C's — clarity, conciseness, correctness, completeness, courtesy, coherence, and concreteness — are applied differently depending on the purpose and context of each letter (Bovée & Thill, 2021, p. 55).
Following your successful performance at the interview held on 10 June 2025, we are pleased to offer you an appointment as Accounts Officer in the Finance and Accounts Department of Zenith Finance Limited.
Your appointment takes effect from 1 July 2025, and the terms and conditions of your engagement are as follows:
1. Salary: You will receive a gross monthly salary of ₦180,000 (One Hundred and Eighty Thousand Naira only), payable on the last working day of each month.
2. Probation: Your appointment is subject to a probationary period of three (3) months, during which your performance will be assessed.
3. Hours of Work: Normal working hours are 8:00 a.m. to 5:00 p.m., Monday to Friday.
4. Reporting Line: You will report directly to the Head of Accounts, Mr. Taiwo Adegoke.
5. Benefits: You will be entitled to leave allowance, health insurance, and pension contributions in accordance with the Company's policy.
Please signify your acceptance of this offer by signing and returning the enclosed duplicate copy of this letter not later than 25 June 2025. Failure to do so will be deemed a rejection of this offer.
We look forward to welcoming you to the Zenith Finance team and trust that your association with our organisation will be mutually rewarding.
I am pleased to inform you that the Hospital Management Board, at its meeting of 5 June 2025, approved your promotion to the rank of Senior Consultant in the Department of Internal Medicine, with effect from 1 July 2025.
This promotion is in recognition of your outstanding clinical performance, dedicated service to this institution over the past seven years, and the commendable research outputs you have contributed to the field of internal medicine. The Board notes with particular satisfaction your role in reducing patient re-admission rates in your unit by 38% over the last two years.
Your revised conditions of service will be as follows:
Grade Level: CONHESS 14
Annual Salary: ₦4,800,000 (Four Million, Eight Hundred Thousand Naira only)
Additional Benefits: Senior staff quarters, research grant access, and enhanced leave entitlement of 30 working days per annum.
Please report to the Human Resources Office on or before 30 June 2025 to complete the necessary documentation. We congratulate you most sincerely and trust that this new responsibility will inspire even greater achievements.
I write with reference to the disciplinary proceedings conducted on 2 June 2025, following a query dated 12 May 2025 regarding the fraudulent alteration of three customer transaction records totalling ₦2,350,000, carried out on 8 May 2025.
Having reviewed your written response to the query, considered all evidence presented at the disciplinary panel hearing, and afforded you the opportunity to defend yourself, the Disciplinary Committee has found you guilty of gross misconduct contrary to Section 14(b) and Section 18(a) of the Bank's Staff Conditions of Service.
Consequently, the Management of First Horizon Bank Nigeria Plc has resolved to dismiss you from employment, with immediate effect from the date of this letter. You are required to:
1. Return your staff identity card, access keys, and all bank property by close of business on 18 June 2025.
2. Clear all outstanding obligations to the Bank.
3. Vacate any staff accommodation provided by the Bank within seven (7) days of this notice.
Your final entitlements — excluding benefits forfeited under the conditions of dismissal — will be processed and remitted to your bank account within fourteen (14) working days.
You have the right to appeal this decision in writing to the Managing Director within seven (7) days of receiving this letter.
I write on behalf of the School Management to formally commend you for the extraordinary results achieved by students in the Mathematics department in the 2024/2025 West African Senior School Certificate Examination (WASSCE).
The Mathematics department recorded a 97% distinction rate — the highest in the school's 32-year history and the second highest in the South-South geopolitical zone. Of the 214 candidates who sat the examination, 207 obtained grade A1. This performance is a direct reflection of your tireless dedication, innovative teaching methods, and the remarkable relationship you have built with your students.
The Management takes particular note of the after-school tutorial programme you introduced without additional remuneration, and the study packs you personally prepared and distributed to students in financial difficulty. These acts of service go well beyond the call of duty and represent the finest tradition of the teaching profession.
This letter will be placed on your permanent staff record. A copy has also been forwarded to the Federal Ministry of Education for national recognition consideration. You are an exemplary model to your colleagues and an inspiration to every student in this school.
It has been brought to the attention of Management that you were absent from your duty post at the Block C construction site from Monday, 3 June 2025 to Thursday, 6 June 2025 (four working days), without obtaining prior approval or providing any notification to your line supervisor, Mr. Emeka Obi.
Your absence during this period resulted in a significant disruption to the project schedule, as the laying of foundation columns — which required your direct supervision — was delayed by three days. This breach of duty is contrary to Section 9(c) of the Company's Staff Handbook, which requires all employees to obtain leave approval not less than 48 hours before any anticipated absence.
You are hereby required to submit a written explanation addressing the following:
1. The reason for your absence from 3 to 6 June 2025.
2. Why you failed to notify your line supervisor or the HR Department prior to or during your absence.
3. Any documentary evidence in support of your explanation.
Your response must reach the undersigned not later than Friday, 20 June 2025. Failure to respond within this period, or the submission of an unsatisfactory explanation, may result in disciplinary action being taken against you in accordance with the Company's disciplinary procedure.
It was with profound sorrow and a heavy heart that I received the news of the passing of your husband, Professor Ikechi Eze, on 14 June 2025. On behalf of the Senate, Management, staff, and the entire University of Port Harcourt community, I extend our deepest and most heartfelt condolences to you, your children, and the entire Eze family.
Professor Eze was not merely a distinguished scholar of African literature — he was a mentor, a builder of young minds, and a voice of uncommon moral clarity in our academic community. His contributions to postcolonial literary theory and his nearly three decades of service to Nigerian scholarship leave a legacy that will endure long beyond his physical presence. The university is immeasurably poorer for his passing.
We recognise that no words can adequately address the weight of the grief you now carry, and we do not presume to lessen it. What we can offer is the assurance of our continued solidarity. You remain a valued and cherished member of this community, and we stand with you in this most difficult season.
Please be assured of our prayers for the repose of his soul and for the strength and comfort of all who loved him. May God grant you and your family the grace to bear this irreplaceable loss.
It is with immense joy and immense pride that the Nigerian Bar Association congratulates you most warmly on your elevation to the distinguished rank of Senior Advocate of Nigeria (SAN), conferred upon you by the Legal Practitioners Privileges Committee on 12 June 2025.
This honour is both richly deserved and long anticipated. Over twenty-two years of outstanding advocacy, you have consistently demonstrated intellectual rigour, unwavering integrity, and an exceptional commitment to justice — qualities that define the finest traditions of the Nigerian legal profession. Your landmark arguments before the Supreme Court in the constitutional cases of 2018 and 2023 have already entered the permanent literature of Nigerian jurisprudence.
Beyond your courtroom achievements, your mentorship of young female lawyers through the Women in Law Initiative has profoundly shaped a new generation of advocates. The SAN rank you now bear is therefore not only a personal accomplishment — it is a recognition shared by every young woman whose career you have touched.
The Nigerian Bar Association is proud to count you among its most distinguished members. We look forward to the continued brilliance that you will bring to our profession and trust that this milestone is but a stepping stone to even greater heights of service to the law and to Nigeria.
Please accept our warmest felicitations. Congratulations, Learned Silk.
The ability to write a letter well is not instinctive — it is a learnable, practicable skill. The principles examined in this lecture — the Seven C's, the distinction between formal and informal correspondence, and the six practical principles of drafting — constitute the foundation on which all written professional communication is built (Bello & Nwosu, 2020, p. 38).
Every letter you write is a record of your intellectual competence and professional character. Know your purpose. Know your reader. Plan. Write clearly. Revise. These are not suggestions — they are the marks of a professional communicator (Adeyemi, 2021, p. 52).
Lecture 1.1 — Principles of Letter Writing
Which of the following best defines a letter in professional communication?
[1 mark]
State and briefly explain any five of the Seven C's of effective letter writing.
[5 marks — 1 per C]
Which complimentary close is correct for a letter saluted "Dear Sir"?
[1 mark]
Distinguish between a formal letter and an informal letter under any four headings.
[4 marks — 1 per heading]
A letter that states "please come sometime soon" violates which quality of a good letter?
[1 mark]
Explain why it is important to know your reader before writing a professional letter. Give one example to illustrate your answer.
[2 marks]
Which of the following is NOT appropriate language in a formal letter?
[1 mark]
Read the following opening sentence and identify all violations of the principles of letter writing: "I am humbly writing to let you know that due to some unforeseen and unexpected circumstances that occurred recently, I might not be able to come for the interview you told me about."
[3 marks]
Why must a writer revise and proofread a letter before sending it? State two specific consequences of sending an unproofread letter in a professional context.
[2 marks]
"A letter is an ambassador." Discuss this statement in relation to the principles of letter writing, and explain what it implies about the standards a professional communicator must maintain.
[3 marks — award: 1 for interpretation, 1 for linking to principles, 1 for quality of argument]
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