The business environment is drastically revolving and changing, so is the tools employed in decision making process. The changing business environment require that organisation achieve more customer satisfaction, exceed shareholder’s expectation, integrated and harmonize all stakeholders’ interest to remain competitive. With the growth in the internet users and application since the last three decades, organization have started shifting focus from offline marketing to online in reaching out to more customers. Online marketing is therefore not seen by many scholars as another form of promotional tools like advertising, personal selling, direct marketing among others but seen as a powerful medium of implementing the various marketing tools online to reach more targeted local and global audience. This research work investigated the effectiveness of online marketing on integrated marketing communication strategy. Specifically, the work aimed at assessing the extent online platform improves the effectiveness of integrated marketing communication strategy. To achieve the objectives of the study, the researcher employed descriptive survey where the marketing/sales department officers of three organization were sampled to collect relevant information regarding the effectiveness of online marketing in actualizing the goal of integrated marketing communication. The organization sampled includes Coca-Cola Nigeria (multinational firm), Uber Nigeria (multinational Firm) and ABC paint (domestic firm) in carrying out the study. Information was obtained from the respondents using questionnaire instrument of data collection using 5 point Likert Scale. The data was analyzed using descriptive statistics (mean, standard deviation, Skewnessetc) and frequencies (percentages, table and graph). From the research findings, it was revealed that online marketing is effective in integrated marketing communication strategy of the organisation by increasing the brand awareness, improves customer satisfaction, easy integration and management, and facilitates automation of marketing activities. It was equally revealed that integrated marketing online effectiveness can be measured using a number of metrics including consumer interaction on site, number of repeated visit, sales volume and profits among others. The researcher also discovered that the trending online marketing tools employed by most organisation includes, e-mail marketing, social media marketing, search engine marketing, artificial intelligence and chartbot among others. It is therefore recommended among others that organizations need to employ various artificial intelligence technology to gather as much information as they can about their customer needs, psychographic, geographic and demographic information to determine what marketing strategy and medium will appeal most to the targeted customers and channel more of the marketing effort towards such direction.