Is “costed” correct?

"Costed" can be used to mean an estimate for how much something costs. For example, "The renovations to the building were costed at approximately $5 million." However, you would be more like to just say "Calculated" or "Estimated." If you hear someone trying to use it as a past tense of "cost," like "Dinner costed $50," that would be wrong.

No. “The book cost $15”. A similar sounding word is accosted, but it’s not even close to the same meaning.

Only in very specific situations where “cost” can become an action verb. Eg in a business office environment, someone may say to a colleague “We need to cost this new project” (find out all the costs involved). The past tense of this would be “I have costed the project”.

In most cases, it’s not appropriate. There is a specific use in regards to financial management of a business activity where the form “costed” is used in estimating. (Per Oxford Dictionary) https://www.oxfordlearnersdictionaries.com/us/definition/english/cost_2

No, but you'll hear it pretty often anyway. The past participle of "cost" is "cost."

I would add, since no one else is coming out and saying it, that this is one of those common "errors"/nonstandard speech patterns that is often associated with class judgment. Putting it more bluntly: if someone says "it costed $5" I immediately assume they are a non-native speaker, have a low level of formal school education, or both. Putting it more bluntly: it makes you sound not very smart.

A similar irregular past tense is “cast”, for most uses the correct past tense of “cast” is “cast” I.e. “she was cast in the role”, “the fisherman cast his line”. But you will very often hear “casted”.

Never

Most people aren't really answering the question here. It's not correct as a past tense of cost. i.e the drink cost £1 not costed. But costed means basically 'worked out the cost of'. I.e. "The project was fully costed" means we know everything that it will cost to make the project happen. It is by its nature past tense.

No. Most grammar on social media is bad or outright wrong, and if you use it you will sound like a foreigner or a native who was never taught proper English

Cost, in the past tense, is syntactically flexible (noun, infinitive, etc) but not structurally flexible. Cost can only be inflected (-ed affix) when used in the same manner as ‘appraised’. It can be inflected for present tense (-s affix) more easily, but is more of a ‘tense’ agreement. The most common verb to use with cost is ‘be’: The cost was $15. These shoes used to cost $50, but now they are on sale for $30. The total will be $40. That’ll be $20. Can you believe how much it costs? (Present) Can you believe how much it cost? (Recent past) How much did it cost? (Recent past) Can you believe how much it used to cost? (Past / distant past).

1. *cost something out* just means to calculate/estimate value of something e.g.: "We costed the price of the project to be twice the initial estimate." 2) *cost something* (be worth some money) e.g.: "This jacket cost me 200 dollars" The first word is a regular tense verb so ends with *-ed* : **present simple:** cost, **past simple:** costed, **past participle:** costed.... The second word is an irregular tense verb and it doesn't follow the *-ed* ending: **present simple:** cost, **past simple:** cost , **past participle:** cost.... The primary confusion is just they're words with two different meanings that have the same exact base word.

You'll also see people using 'casted' when in fact it's simply just 'cast'.

No. It’s not in everyday speech. “The shirt cost $30 yesterday, but today it costs $40!” Cost is the past tense of cost. 

Cost is the past tense and past participial too

It's very much used in business and accounting, but should not be used much in standard casual speech. That said, some American dialects might use it more often in casual speech.

Without the context it's impossible to say whether the usage was correct.

In accounting-speak, it can be used as an alternative to 'priced out', "I've costed out the contribution we must make toward the reception..."

In a rather uncommon/old fashioned usage it exists. As a way to joke around it & other obvious mistakes are at times used. Otherwise & in the majority of uses it's not correct.

I'm an IT guy who's spent decades in Finance. The past tense of Cost is Cost. This shirt cost $20 last year, but this year, it costs $30. The shirt used to cost $5 to manufacture, but this year it costs $7.50, and we're getting killed on the margin, but that's all the market will bear. The act of performing an analysis as to how to price something is "costing". The past tense of costing is costed. Billy asked me to do the costing on this estimate. At first, I thought it was going to be a $10K job, but it turns out that the footers are going to need to go a lot deeper to support that elephant pool, and after I ran the numbers, it's going to be $15K for sure. "Hey, why is this estimate at $15K?" "I costed it yesterday, the footers are going to suck. They need a pile driver and structural steel."

Wow this thread is surprising to me, I’m a native speaker and I have been saying “costed” my whole life. I’ve never heard of any rule that it is incorrect to say something like “Dinner last night costed $15.” Is this something that is commonly said in the US South, or did I just miss the day where we learned this rule in school?

So are some of you saying that phrase, "the project was costed at $XXX" is basically the same as saying "the project estimate was $XXX"? Works for me, but"my new purse costed $XXX" just doesn't work for me.

"Costed" is correct, but only in specific cases! Normally, the past tense of "cost" is just "cost" (e.g., *"The book cost $20."*). But when referring to calculating expenses, "costed" works (e.g., *"The project was costed before approval."*). Want to master tricky English rules like this? Check out **[English Mastery Fun][English Mastery Fun!](https://www.youtube.com/channel/UCNXvrsbLEg2FuB-BOhsG-3g?sub_confirmation=1)—fun quizzes, smart explanations, and everything you need to sharpen your skills!

Technically, it's correct because you understood what they meant (past tense of cost) and some dialects do overgeneralize the -ed particle on some words that other dialects don't. I would say use depends on where you live and if the people around you say it, don't worry about it, but if people around you don't use, I would not use it.

It is a word, but it is often used incorrectly. It's not used in the sense of a normal purchase "cost" of something. It is used as the past tense of a price estimate. "The bathroom repairs were costed at $1000". It's relatively uncommon.

The past tense is cost. Costed is not correct but I hear it often. 

99% of the time no it's not. But it's understood and it's a pretty common mistake. There is a niche/uncommon usage of the word "cost" meaning to estimate the price of something, and that WOULD be "costed" in past tense. But the overwhelming majority of the time people use that word to refer to how much was paid for something and in that case the correct past tense is still "cost"