As a small-business owner, you are inundated with demands on your time. While tackling tasks in the order they are due may seem like a logical approach, the time to start a task should not be based solely on when it's due. You not only have to know when it's due, but also how long it will take. If you don't factor in both, you're likely prioritizing urgent tasks over the ones that are most critical to your business. Here are three ways to reassess your priorities, and make sure you never fall behind.

1. Break down big projects into small tasks with staggered deadlines.

The most important work you need to do for your business is likely contained in a handful of extended projects or product development cycles that stretch over weeks, if not months. Yet your impulse likely is to prioritize the task due two days from now over the big project deliverable due in three months, because it feels time-sensitive while the project does not. But what if the task due in two days takes just five minutes to complete, while the project due in three months is already two weeks behind schedule and will require 40 hours of work per week to deliver it anywhere close to on time?

The Project Management Institute's annual report shows companies lose 12 percent of their investment in projects every year because of poor performance. This is in part because project managers and staff are under the illusion they have a lot of time when they don't. Big tasks with far-out due dates seem lower priority when you think about them as a single task with a single due date that is nowhere close to today. To avoid this, break them down into bite-size tasks and assign each one its own due date. The project may be due in three months, but if one of the sub-tasks needs to be done today, then the sub-task is higher priority than the five-minute task due tomorrow.

2. Prioritize tasks that depend on other people.

As a business owner, many of your most important tasks will involve engaging your leadership team and employees. For example, which would you consider the higher priority: reaching out to potential sales prospects for sales targets you are trying to hit next month or finishing the pitch deck for next week's angel investor conversations?

Given its importance, more immediate due date, and your critical role in its creation, the pitch deck seems higher priority, but you actually want to do the outreach first. You must assume tasks that depend on other people, like sales conversations, will take longer than tasks you can do yourself. If not, you may find yourself in a tough situation as a deadline approaches because you waited until the last moment to connect with someone that you needed something from to finish the task.

When estimating how long tasks will take you, be sure to include waiting time to get what you need from each round of communication. The more senior or high profile the individuals you dependent on are, the more time you'll need to budget as well. Similarly, the less control you have over the people your task depends on, like those sales prospects, the longer the delays you must consider.

3. If you're not sure how long a task will take, start it early.

In business, especially as a startup, you're constantly forced to tackle tasks you haven't done before. When faced with the choice between prioritizing a task you've done before that is due soon and a task you haven't done before that is due later, your first impulse is likely to prioritize the task due sooner.

But my coaching conversations have found that people are not naturally good at estimating how long work will take them.

The smallest unexpected obstacles or distractions can turn a half-day task into a day-and-a-half task. While adding a buffer of 10 to 15 percent to tasks of uncertain duration is helpful, you'll also want to prioritize these tasks higher so you have time to compensate if your estimate is wildly wrong.

Making decisions about what to do first might seem simple, but it's actually pretty complex. Using these three simple strategies can go a long way in making the time for your company's highest priorities, and ultimately help grow your business.