Signal words are the small words and phrases that tell your reader how one idea relates to the next: however, therefore, for example, first, in short. They work like road signs. When your reader sees however, they expect a turn. When they see as a result, they expect a consequence. Pick the right one and your essay reads as one connected argument instead of a stack of separate points.

Below you'll find signal words sorted by function, the punctuation rules behind most comma splices, how to use signal phrases to introduce quotes in MLA and APA, and a before-and-after paragraph.

What Are Signal Words?

Signal words are words and phrases that show the logical link between ideas, such as addition, contrast, cause and effect or order. A Cal Poly Pomona guide to recognizing transitions or signal words puts it in one line: "Transitions (or signal words) are words and phrases that show the connection between ideas."

You'll see the same words called transition words, transitional expressions, linking words or connectors. The labels overlap almost completely, so focus on the job each word does. The UNC Writing Center's handout on transitions describes them as "words with particular meanings that tell the reader to think and react in a particular way to your ideas." That's why swapping therefore for however changes your meaning, not just your style.

Signal Words vs. Transition Words vs. Signal Phrases

Signal words and transition words are nearly the same thing, but signal phrases do a different job: they bring someone else's words or ideas into your paper.

Term	What It Does	Example
Signal words	Show how your own ideas relate	As a result, attendance fell.
Transition words	The same job, usually linking sentences and paragraphs	Furthermore, the survey was anonymous.
Signal phrases	Introduce a quote, paraphrase or summary and name its source	According to Naomi Baron, reading is ...

The Purdue OWL page on signal and lead-in phrases describes them as expressions that "usually occur in the parts of sentences that come just before quotes and paraphrases." The MLA and APA section below covers them in full.

Why Signal Words Matter When You Read

Signal words help you read faster because they show where the writer is heading. The Cal Poly Pomona guide notes that "Contrast words signal a change in the direction of the writer's thought." A paragraph that opens with in contrast is about to give you the other side, and a list that starts with first tells you to look for second and third.

Signal Words Examples by Function

The fastest way to choose a signal word is to name the relationship first, then pick a word from that row. Use this table as a quick reference, and use the detailed tables below when two words look interchangeable but aren't.

Function	What It Tells the Reader	Common Signal Words
Addition	Another point is coming in the same direction	also, in addition, furthermore, moreover, another
Contrast	The direction is about to change	however, but, yet, although, in contrast, nevertheless
Concession	You're granting a point before you push back	admittedly, granted, of course, even though
Comparison	Two things are alike in some way	similarly, likewise, in the same way, just as
Cause and effect	One thing leads to another	because, since, therefore, as a result, consequently
Sequence and time	Here is the order	first, next, then, meanwhile, finally
Example	A specific case is coming	for example, for instance, such as, to illustrate
Clarification	The same idea, said more plainly	in other words, that is, namely
Emphasis	This point matters most	indeed, in fact, above all, especially
Conclusion and summary	The discussion is wrapping up	to sum up, in short, overall, ultimately

Lists vary a little from source to source. UNC's handout, for instance, adds place words such as above, below and nearby for descriptive writing. Treat the categories as a tool for choosing, not a rule to memorize.

Signal Words That Add, Compare and Contrast

Addition, comparison and contrast words do most of the work in body paragraphs, because most paragraphs either stack up evidence or weigh one side against another.

Addition Signal Words

Addition signal words tell the reader that the next point supports the same claim.

Signal Word	Best Use	Example Sentence
also	A plain, neutral addition that works mid-sentence	The survey also asked how many hours students worked.
in addition / additionally	A separate point of similar weight	In addition, the program shortened wait times for advising.
furthermore	A formal addition that builds on the last point	Furthermore, the policy covers part-time students.
moreover	A point that makes the case stronger	Moreover, the fee falls hardest on first-year students.
another	A new reason or example in a topic sentence	Another reason to keep the library open late is exam week.
equally important	The next point carries the same weight	Equally important, the plan does not raise tuition.

Contrast Signal Words

Contrast signal words tell the reader that the next idea pushes against the last one. Watch the grammar here, because words with the same meaning follow different rules.

Signal Word	Best Use	Example Sentence
however	A clear turn between two sentences or clauses	The sample was large. However, it came from one campus.
but / yet	A turn inside one sentence, with a comma when it joins two full clauses	The plan is cheap, but it is slow.
although / even though	Putting the weaker idea in a dependent clause	Although the plan is cheap, it is slow.
in contrast / by contrast	Showing a difference between two subjects	The state college raised fees. In contrast, the community college froze them.
on the other hand	A second side, after you've laid out the first	On the other hand, online classes cut commuting time.
nevertheless / nonetheless	Admitting a point, then continuing anyway	The data are limited. Nevertheless, the trend holds in every year.
on the contrary	Correcting a false idea, not just adding a different one	The change did not save money. On the contrary, it raised costs.
despite / in spite of	Contrast followed by a noun phrase, not a full clause	Despite the cost, the board approved the plan.

Concession is a special kind of contrast. Words like admittedly, granted and while it is true that let you give the other side a point before you answer it, which is the backbone of a counterargument paragraph in an argumentative essay.

Comparison Signal Words

Comparison signal words show that two ideas, people or results are alike in some way.

Signal Word	Best Use	Example Sentence
similarly	Opening a sentence that mirrors the last one	Similarly, the second study found no effect on grades.
likewise	A parallel case; slightly more formal	Likewise, the nursing program saw higher retention.
just as ... so too	A two-part comparison inside one sentence	Just as the novel questions wealth, so too does the film.
both ... and	Pairing two subjects with the same trait	Both the poem and the speech rely on repetition.

For a fuller set built for side-by-side papers, see our list of transition words for a compare and contrast essay.

Signal Words for Cause, Effect and Order

Cause-and-effect and sequence words carry the logic of an argument or a process, so they are where the wrong choice does the most damage. A therefore claims that your last sentence proves your next one. Make sure it does.

Cause and Effect Signal Words

Some cause and effect signal words introduce the cause, and others introduce the result. Keep the two groups straight.

Signal Word	Introduces	Example Sentence
because / since	The cause, as a full clause	Attendance fell because the bus route changed.
because of / due to	The cause, as a noun phrase	Attendance fell because of the new bus route.
therefore / thus	A logical conclusion; formal	The sample was small; therefore, the results are tentative.
as a result / consequently	A result that followed from events	The route changed. As a result, attendance fell.
so	A result inside one sentence; plain but correct	The library closed early, so students moved to the student center.
for this reason	A decision tied to a reason you just gave	For this reason, the researchers repeated the study.

Watch since. It can mean "because" or "from the time that," so a sentence like "Since the policy changed, complaints have doubled" can be read two ways. If you mean cause, because is clearer.

Sequence Signal Words

Sequence signal words put steps, events or reasons in order, which makes them essential in process essays, narratives and lab reports.

Signal Word	Best Use	Example Sentence
first, second, third	Numbered reasons or steps	First, the policy is affordable.
next / then	The following step	Next, record the temperature every minute.
after that / afterward	A step that comes once another is done	Afterward, the class compared results.
meanwhile / at the same time	Two things happening at once	Meanwhile, the control group received no feedback.
previously / earlier	Stepping back in time	Previously, the college required two placement tests.
subsequently	A formal "later"	The bill subsequently passed the Senate.
finally / last	The final step or reason	Finally, the plan is easy to reverse.

Keep a sequence consistent. If you open with first, follow with second and third instead of switching to a different pattern halfway through.

Signal Words for Examples, Emphasis and Conclusions

These signal words tell the reader how to weigh what comes next: as proof, as the main point or as the wrap-up.

Example and Clarification Signal Words

Signal Word	Best Use	Example Sentence
for example / for instance	A full example sentence	For example, the 2020 survey had no rural respondents.
such as / including	Examples listed inside a sentence	Fees such as parking and lab charges add up.
specifically / in particular	Narrowing a general claim	Specifically, the effect appeared only in math courses.
namely	Naming exactly what you just referred to	The study had one flaw, namely its small sample.
in other words / that is	Restating an idea more plainly	In other words, the policy helps only full-time students.

In APA papers, keep the abbreviations e.g. and i.e. inside parentheses. APA's guidance on Latin abbreviations says to use them "only in parenthetical material; in the narrative, use the translation of the Latin term," which means writing for example and that is in your sentences.

Emphasis Signal Words

Signal Word	Best Use	Example Sentence
indeed	Confirming and strengthening the last point	Indeed, the gap widened every year.
in fact	Adding a fact that goes further than expected	In fact, enrollment doubled.
above all / most importantly	Marking your strongest point	Above all, the plan protects students' privacy.
especially / particularly	Pointing to the case that matters most	The rule hurts commuters, especially those who work.
undeniably / without a doubt	Only when your evidence is overwhelming	Undeniably, the speech changed public opinion.

Use emphasis words sparingly. If every point is "most important," none of them is.

Conclusion and Summary Signal Words

Signal Word	Best Use	Example Sentence
to sum up / to summarize	Pulling several points together	To sum up, the policy is cheap, fair and easy to reverse.
in short / in brief	A one-sentence version of the argument	In short, later start times work.
overall / on the whole	A balanced judgment after mixed evidence	Overall, the benefits outweigh the costs.
ultimately	The final, most important outcome	Ultimately, the decision belongs to voters.
to conclude	A formal closing signal; use once	To conclude, the evidence supports a later start.

A conclusion signal word promises that you're done adding new evidence, so don't follow it with a new argument. For more ways to open that last paragraph, see how to start a conclusion paragraph.

How to Punctuate Transition Words

How you punctuate transition words depends on their grammar, not their meaning. However and although both signal contrast, but they need different punctuation, and mixing them up causes a lot of comma splices.

Word Type	Examples	Pattern	Example Sentence
Conjunctive adverb joining two clauses	however, therefore, moreover, consequently, thus	Clause; word, clause.	The sample was small; however, the effect was large.
Transition opening a sentence	however, for example, as a result, in addition	Word, clause.	However, the effect was large.
Transition interrupting a clause	however, therefore, for example	Commas on both sides	The effect, however, was small.
Coordinating conjunction	and, but, for, or, nor, so, yet	Clause, word clause.	The sample was small, but the effect was large.
Subordinating conjunction	because, although, since, while, if, when	Comma after the dependent clause when it comes first; usually none when it comes second	Although the sample was small, the effect was large.

These patterns follow the Purdue OWL's sentence punctuation patterns, where words like therefore and however are "independent markers" that take a semicolon before and a comma after when they join two independent clauses. Purdue's extended rules for commas add that introductory words such as however are followed by a comma, and that a word interrupting the middle of a sentence gets "a pair of commas," as in "She was, however, too tired to make the trip."

The classic error is the comma splice: "The sample was small, however, the effect was large." That joins two complete sentences with only a comma. Fix it with a period or a semicolon before however.

How to Use Signal Phrases to Introduce Quotes in MLA and APA

A signal phrase introduces a quote, paraphrase or summary by naming the source and setting it up, so your reader always knows where your ideas stop and the source's begin. Blinn College's writing center page on signal phrases and verbs, drawing on A Writer's Reference, says a signal phrase "usually names the author of the source," "provides some context for the source material" and "helps readers distinguish your ideas from those of the source."

What Goes into a Signal Phrase

Who said it. Give the author's full name on first mention and the last name after that. If there's no author, use the organization's name or the title of the work.
Context, when it helps. A detail such as "in a 2013 PMLA article" tells your reader why the source matters.
A precise verb. Argues, notes and disputes each describe a different stance.

The MLA Style Center's lesson on integrating quotations in research writing breaks the process into four moves: introduce the source with a clear subject and a precise verb; quote, paraphrase or summarize; cite; and connect the evidence to your main idea. Don't skip the last one. UNC's handout on quotations compares each quote to "the filling in a sandwich": it needs your own words on both sides.

MLA Signal Phrases

In MLA style, signal phrases usually use the present tense, and once you name the author in the sentence, the parentheses hold only the page number. The MLA Style Center's overview of in-text citations gives this example:

According to Naomi Baron, reading is "just half of literacy. The other half is writing" (194).

Without the signal phrase, the author's name moves into the parentheses: (Baron 194). MLA marks it wrong to name Baron in both places. The matching works-cited entry is: Baron, Naomi S. "Redefining Reading: The Impact of Digital Communication Media." PMLA, vol. 128, no. 1, Jan. 2013, pp. 193–200.

On tense, MLA's post on using the present tense with works says, "It is customary to use the present tense when discussing a literary work," and it extends the principle to criticism and to authors when their work is implied. Switch to the past tense for historical facts, such as when a play was first performed, and stay consistent. For the rest of the format, see our MLA style guide.

APA Signal Phrases

In APA style, signal phrases usually take the past tense or present perfect, and the publication year follows the author's name. APA's guidance on verb tense recommends the past tense ("Martin (2020) addressed") or the present perfect ("researchers have studied") when you discuss other researchers' work in a literature review. Its page on quotations requires a page number or other location for every direct quote. Here is the same source in APA:

Baron (2013) argued that reading is "just half of literacy. The other half is writing" (p. 194).

With a parenthetical citation instead, it becomes: Reading is "just half of literacy. The other half is writing" (Baron, 2013, p. 194). A quote of 40 words or more turns into an indented block quotation without quotation marks. For paraphrases, APA's paraphrasing guidance makes the page number optional, though adding one helps a reader find the passage in a long work. Our APA style guide covers the reference list and paper format.

Signal Verbs by Stance

The verb in your signal phrase tells the reader what the source is doing, so it should match the source's actual position. Blinn's handout separates "more objective" verbs (illustrates, indicates, states, suggests) from "more weighted" ones (charges, complains, asserts, insinuates), and it flags says as overused.

Stance	Signal Verbs	Watch Out For
Neutral reporting	states, notes, explains, describes, observes, points out	Safe defaults; vary them
Making an argument	argues, asserts, contends, maintains	Only when the source takes a position
Tentative	suggests, implies, proposes, speculates	Right for hedged findings; don't upgrade them to "proves"
Agreeing or building on	agrees, confirms, supports, extends, acknowledges	"Acknowledges" implies the source concedes a point
Disagreeing	disputes, challenges, questions, rejects, refutes	"Refutes" means the source proved a claim wrong; use "disputes" if it only argues against it
Reporting findings (APA)	found, showed, reported, demonstrated, concluded	Past tense in APA: "Martin (2020) found"

The same verbs work when you paraphrase instead of quoting; see how to paraphrase without plagiarizing for the rest of that process.

Where to Put a Signal Phrase

A signal phrase can open the sentence, interrupt it or set up a colon, and varying the position keeps a source-heavy paragraph from sounding repetitive. Here is the Baron quote in MLA form three ways:

Opening: As Naomi Baron notes, reading is "just half of literacy. The other half is writing" (194).
Interrupting: Reading, Naomi Baron argues, is "just half of literacy. The other half is writing" (194).
After a colon: Naomi Baron puts the point simply: reading is "just half of literacy. The other half is writing" (194).

UNC's quotations handout adds three punctuation habits: use a colon after a complete sentence, skip the comma when that follows your verb, and put the citation after the closing quotation mark but before the final period.

Signal Words in Action: A Before-and-After Paragraph

Signal words turn a list of true statements into an argument. Here is a body paragraph on school start times, written first without them. Its facts come from a CDC report on middle and high school start times.

Before:

Middle and high schools should start later. In puberty, sleep rhythms commonly shift. Adolescents become sleepy later at night and need to sleep later in the morning. A 7:30 a.m. class cuts into the sleep they need. In 2014, the American Academy of Pediatrics recommended that middle and high schools start no earlier than 8:30 a.m. Some districts worry that new bus schedules will raise transportation costs. A scheduling problem is not a good reason to ignore a health recommendation.

After:

Middle and high schools should start later because early bells work against teenagers' biology. In puberty, sleep rhythms commonly shift, so adolescents become sleepy later at night and need to sleep later in the morning. As a result, a 7:30 a.m. class cuts directly into the sleep they need. For this reason, the American Academy of Pediatrics recommended in 2014 that middle and high schools start no earlier than 8:30 a.m. Admittedly, some districts worry that new bus schedules will raise transportation costs. Even so, a scheduling problem is not a good reason to ignore a health recommendation.

Signal Word	Function	What It Adds
because	Cause	Gives the claim its reason
so	Effect	Links the body clock to bedtime
As a result	Effect	Makes lost sleep a consequence
For this reason	Cause and effect	Frames the AAP advice as a response
Admittedly	Concession	Grants the main objection
Even so	Contrast	Returns to the claim

The facts are the same in both versions. What changed is that each sentence now tells the reader how it connects to the one before it. Notice, too, that two signal words sit inside sentences rather than at the start, which keeps the paragraph from sounding mechanical.

Common Mistakes with Signal Words

The most common mistake with signal words is using one that claims a relationship your sentences don't actually have. Check your draft for these six problems when you revise.

Wrong logic. "The survey had 40 responses. Therefore, the policy works." Nothing in the first sentence proves the second. Save therefore for real conclusions.
A signal word on every sentence. Opening every sentence with moreover or furthermore sounds padded. UNC's transitions handout puts it plainly: "Transitions cannot substitute for good organization, but they can make your organization clearer and easier to follow."
Generic paragraph transitions. "Another point is" could connect any two paragraphs. The Purdue OWL's guide to writing transitions advises, "It is a good idea to continue one paragraph where another leaves off." Echo the idea that closed the last paragraph in the first sentence of the next. Our guide to paragraph starters for essays has more options.
Dropped quotes. A quote standing alone as its own sentence leaves the reader guessing who said it and why. Add a signal phrase before it and your own comment after it.
Ambiguous words. Since can mean "because" or "from the time that," and while can mean "during the time that" or "although." If both readings fit your sentence, use because or although instead.
A verb that misstates the source. Writing "Smith proves" when Smith only suggests overstates the evidence. Match the verb to the source's confidence.

If you'd like a second set of eyes on how your own draft flows, you can ask a tutor for feedback on your essay, including notes on where a signal word helps and where it gets in the way.

Frequently Asked Questions

What Are 10 Examples of Signal Words?

Ten common signal words are also, furthermore, however, although, similarly, because, therefore, first, for example and finally. Each tells the reader something different. Also and furthermore add a point, however and although mark a contrast, similarly marks a likeness, because and therefore show cause and effect, first and finally show order, and for example introduces evidence. Choose by the relationship you mean, not by how formal the word sounds.

What Is the Difference Between Signal Words and Transition Words?

In most classes there is no real difference. Both terms describe words such as however, therefore and for example that show how ideas connect. You'll often see "signal words" in reading and study-skills materials and "transition words" in writing handouts, but the lists are largely the same. Signal phrases are the outlier: they introduce a quote, paraphrase or summary and name its source, as in "According to Baron."

What Is a Signal Phrase in MLA?

In MLA style, a signal phrase is the part of your sentence that names the source before a quote or paraphrase, such as "According to Naomi Baron" or "Baron argues." Because the author is already named, the parenthetical citation holds only the page number, as in (194). MLA writers usually put the verb in the present tense when discussing a written work, and they avoid naming the author in both the sentence and the parentheses.

Should Signal Phrases Be in Past or Present Tense?

It depends on the citation style. APA recommends the past tense or present perfect when you discuss other researchers' work, as in "Baron (2013) argued" or "researchers have found." MLA customarily uses the present tense for written works, as in "Baron argues," but switches to the past tense for historical facts, such as when a play was first performed. Whichever style you follow, keep the tense consistent within a paragraph.

Can You Start a Sentence with However?

Yes. When however means "on the other hand," you can open a sentence with it and follow it with a comma: "However, the results were mixed." What you can't do is join two complete sentences with however and a comma alone, because that creates a comma splice. Put a period or a semicolon before it instead. When however means "no matter how," as in "However hard you try," no comma follows it.

How Many Transition Words Should You Use in an Essay?

There is no set number. Use a transition word when the connection between two sentences or paragraphs isn't already obvious, and skip it when it is. A quick test is to read a paragraph aloud. If most sentences open with a signal word, cut some or move them inside the sentence. Strong paragraphs also connect ideas by repeating a key term from the sentence before, which needs no transition word at all.

What Are Signal Words in Reading?

In reading, signal words are clues to how a text is organized. Words like first, next and finally point to a sequence. However and in contrast point to a comparison, and because and as a result point to cause and effect. Spotting them as you read helps you predict what comes next, find the main points faster and take notes that follow the author's structure.

Signal Words and Phrases: List and Examples for Essays