If there is one grammar rule that separates intermediate learners from advanced speakers, it is the correct use of Since and For. In the Indian context, these two words are often translated similarly in regional languages, leading to the very common mistake:
“I am working here since five years.”
At 99Learners, we want to help you fix this once and for all. By the end of this guide, you will know exactly which one to use in every situation.
Table of Contents
FOR vs SINCE Rules in Grammar
1. The Golden Rule: Point vs. Period
The simplest way to remember the difference is to look at the “type” of time you are describing.
Use FOR for a Period of Time
“For” measures the duration—how long something has been happening. It looks at the whole “chunk” of time.
Examples: For 20 minutes, for three days, for six months, for a long time.
The Formula:
FOR + A Number + Time Unit
Use SINCE for a Point in Time
“Since” marks the starting point—when the action began. It looks back to a specific moment in the past.
Examples: Since 9:00 AM, since Monday, since January, since I was a child.
The Formula:
SINCE + Specific Starting Point
2. Common Mistakes (and How to Fix Them)
Let’s look at the errors we frequently see in business emails and IELTS essays.
| Incorrect (The “Indianism”) | Correct (Standard English) | Why? |
|---|---|---|
| I am living here since 2010. | I have been living here since 2010. | “Since” requires a Perfect Tense (have been). |
| He is waiting for two hours. | He has been waiting for two hours. | You cannot use simple continuous with “for” in this context. |
| I haven’t seen her since a long time. | I haven’t seen her for a long time. | “A long time” is a duration, not a starting point. |
| We are friends since school days. | We have been friends since school days. | “Since” connects the past to the present, so Perfect Tense is needed. |
3. The “Perfect Tense” Connection
This is the most important technical part: Since and For are almost always used with the Present Perfect or Present Perfect Continuous tenses.
Wrong: I work here for five years. (This sounds like a habit, not a duration).
Right: I have worked here for five years.
Right: I have been working here for five years.
Pro Tip for Learners in 2026:
When you are talking about a project that is still happening right now, use the Present Perfect Continuous (have been + ing).
Example: “We have been providing free resources since the start of the year.”
4. Since vs. For: The Reference Table
Use this table as a quick “cheat sheet” when you are writing:
| Use FOR with… | Use SINCE with… |
| 10 Seconds | 10:30 PM |
| 30 Minutes | Breakfast time |
| 5 Days | Monday |
| 2 Weeks | January 1st |
| 4 Months | Last Christmas |
| 10 Years | 2015 |
| A Century | I left college since … |
| “A long time” | The beginning of time |
5. Can “Since” be used in other ways?
Yes! In advanced English, “Since” can also mean “Because.”
Example: “Since it is raining, we should stay indoors.”
However, when you are talking about Time, always stick to the “Starting Point” rule.
10 Usage Examples of FOR and SINCE
| No. | FOR (Duration) | SINCE (Starting Point) |
|---|---|---|
| 1 | I have lived here for five years. | I have lived here since 2019. |
| 2 | She has been studying for two hours. | She has been studying since 3 PM. |
| 3 | They have known each other for a long time. | They have known each other since childhood. |
| 4 | He has worked here for six months. | He has worked here since July. |
| 5 | We have been waiting for thirty minutes. | We have been waiting since morning. |
| 6 | I have not seen her for three days. | I have not seen her since Monday. |
| 7 | The baby has been crying for an hour. | The baby has been crying since noon. |
| 8 | It has been raining for two days. | It has been raining since yesterday evening. |
| 9 | He has been practicing yoga for a year. | He has been practicing yoga since 2024. |
| 10 | She has felt sick for a week. | She has felt sick since last Friday. |
Other Uses of FOR and SINCE
FOR
1. To Show Purpose (Meaning: in order to) – Example: This knife is for cutting vegetables.
2. To Show Benefit (On behalf of someone) – Example: I did this for you.
3. To Show Exchange (In return for) – Example: I bought this phone for ₹10,000.
4. To Show Support or Preference – Example: He voted for the new policy.
5. To Show Function or Use – Example: What is this tool for?
6. To Show Reason – Example: He was punished for cheating.
SINCE
1. Since = Because (Reason) – Example: I stayed home since I was sick.
2. From a Past Time Until Now – Example: I met him in 2020 and have liked him ever since.
3. Ever Since (Strong Emphasis) – Example:Â I have loved English ever since I was a child.
4. Since + Clause (Starting Event) – Example:Â It has been two years since we moved here.
As you know, FOR and SINCE are used as prepositions and conjunctions. Below is the master chart of all use cases of FOR and SINCE, as requested by our students at 99Learners.
Complete Master Chart – FOR
| Category | Meaning | Formula | Example |
|---|---|---|---|
| Duration | Period of time | for + time period | She lived there for 5 years. |
| Distance | Length of space | for + distance | We walked for 3 km. |
| Purpose | In order to | for + noun / V-ing | This knife is for cutting. |
| Benefit | On behalf of | verb + for + person | I did this for you. |
| Exchange / Price | In return for | verb + for + amount | I bought it for ₹500. |
| Reason | Because of | adj/passive + for + noun | He was punished for cheating. |
| Support | In favour of | be + for | I am for the proposal. |
| Destination | Heading toward | leave/head + for + place | She left for Delhi. |
| Occasion | Event purpose | for + event | She dressed up for the party. |
| Representation | On behalf of | verb + for + group | He spoke for the team. |
| Conjunction (Formal) | Because | clause, for + clause | I left early, for I was tired. |
Complete Master Chart – SINCE
| Category | Meaning | Formula | Example |
|---|---|---|---|
| Starting Point | From specific time | since + point in time | I have lived here since 2020. |
| Since + Clause | From past event | since + subject + verb | I have been happy since I met you. |
| It has been… since | Time passed | It has been + time + since + clause | It has been 2 years since we met. |
| Ever Since | Strong emphasis | ever since + clause | I have loved music ever since childhood. |
| Standalone Since | From then until now | … since | He left in 2022 and hasn’t returned since. |
| Since = Because | Reason | since + clause | Since it was raining, we stayed home. |
| Question Structure | Time gap question | How long has it been since…? | How long has it been since you saw him? |
Test Your Knowledge: A Mini-Quiz
Fill in the blanks with either Since or For. (Correct answers after the questions)
I have been studying English ______ three hours.
She hasn’t eaten anything ______ yesterday morning.
We have lived in this city ______ 2018.
The AI has been processing the data ______ a few seconds.
He has been a teacher ______ he graduated.
(Answers: 1. For, 2. Since, 3. Since, 4. For, 5. Since)
