If everyone lies—and no one enjoys being lied to—why is dishonesty so common in romantic relationships? From harmless white lies to life-altering secrets, deception often finds its way between partners, and it never feels good.

Is lying so ingrained in human behavior that people do it without realizing? Research suggests that nearly 60% of adults can’t go more than ten minutes without telling a lie. While most of these untruths are minor, it raises an important question: if they’re so insignificant, why tell them at all? Interestingly, participants in the study were genuinely surprised when they later watched recordings of their conversations and realized how frequently they had lied.

So why do people lie in relationships? And is there ever a justifiable reason for it? Let’s explore the psychology behind deception and uncover the most common reasons partners are dishonest.

People lie about both small and serious matters. Once we understand the difference between a harmless fib and a relationship-shattering secret, it becomes easier to see why lying happens in the first place. Below are the most common reasons.

# Cheating

According to academic researcher Tom Smith, around 15–18% of married couples experience infidelity at some point. In today’s digital age, with messages, apps, and online trails, getting away with cheating has become increasingly difficult.

Even if the truth doesn’t surface immediately, it usually does eventually. Infidelity remains one of the most damaging secrets in a relationship, often leading to broken trust, emotional trauma, financial fallout, and fractured families. Trust is easy to give when love is strong—but once it’s lost, rebuilding it can feel almost impossible.

# Insecurity

A study cited by Scientific American found that nearly 90% of people lie on their online dating profiles. These lies often stem from insecurity.
Women may misrepresent their weight, while men often exaggerate their height or income. Others lie about their careers, education, or family dynamics—all in an effort to appear more desirable or avoid judgment.

# Avoiding Accountability

Think back to childhood—being asked who made a mess and instinctively saying, “Not me.” That impulse doesn’t always disappear with age. One of the most common reasons people lie is to dodge responsibility.

According to psychologist Dr. Phil, men are more likely to lie to avoid accountability, while women tend to lie to spare someone’s feelings. Statements like “I never said that” or “I didn’t spend that money” are often used to escape conflict or consequences.

# Money Matters

Finances are a sensitive topic in many relationships, especially when partners maintain separate accounts. From hiding shopping receipts to concealing credit card statements, financial dishonesty is more common than people admit.

A credit card survey revealed that 6% of respondents hid bank or credit card statements from their spouse. One in five felt it was acceptable to conceal a $500 purchase, and some even admitted to keeping secret bank accounts.

# To Seem More Interesting

For some, exaggeration and drama make life feel more exciting. People may lie about their travel experiences, romantic history, or celebrity encounters to appear more intriguing or impressive than they really are.

# Lying About Family

Family situations can be complicated and deeply personal. Many people lie to avoid embarrassment or protect loved ones, especially when dealing with absent parents, addiction, mental health struggles, or estranged relationships. Sometimes, silence or fabrication feels easier than explaining painful truths.

# To Hurt Their Partner

Spite can fuel dishonesty. If someone feels hurt or betrayed, they may lie out of revenge—for example, claiming infidelity or romantic interest from someone else just to provoke jealousy or pain.

# To Avoid Hurting Their Partner

On the flip side, many lies are told to spare feelings. Statements like “You never annoy me” or “You’re the best I’ve ever had” may not always be true, but they’re often said to preserve harmony and protect egos—especially when the truth would serve no constructive purpose.

# To Protect Others

People also lie to shield friends or family. This can include covering for a friend’s whereabouts, vouching for someone on applications or legal matters, or keeping private information confidential. These lies are often motivated by loyalty or a desire to protect someone from harm or scrutiny.

# To Manipulate

Some lies are told purely to control or influence. For instance, falsely accusing a friend of inappropriate behavior to drive a wedge between them and a partner is a form of manipulation. This kind of deception is particularly harmful, as it damages relationships and trivializes serious issues.