Step parents should not contribute one penny to the support of skids. Anything they DO contribute should be voluntary.

When my DH was paying CS, it was $1500 a month for 2 skids AND he had to carry them on his insurance. He was living paycheck-to-paycheck because of that.

Interesting question.

A good one would be, what would be fair? I teach math, I like questions like this. 

Assuming the mother and father are both single with one child, and mortagages are fairly similar.

(Bills = (Mortgage or rent + 1/2groceries + mutually approved expenses) / 365) x (number of days in possession of child))

Total child support determined by (Bills(custodial) / 2) - (Bills(NCP) / 2).

That seems like it'd be fair. Lol.

$546/month, 1 kid. Custody order is 50/50 (2009) but CS is based upon what is ACTUALLY happening (recalculated 2018) which is 82%/18%, sometimes more like 90%/10%. California, looks at income equalization in regard to time spent in each home.

My DH pays $888 a month in CS and then around $250 more in extras for whatever crap BM signs SD up for.

I don't pay for anything for SD but DH will stick me for household bills so I end up indirectly paying....

DH pays $1027/ mo CS plus $25/wk for health insurance for one lazy, Failure to Launch almost 20 year-old, for 13 more months! 

We are frugal and live way below our take home income, so it doesn't really affect us much. 

My DH does not pay or receive CS.  We have 50/50 custody. Under our state laws BM could get CS because DH makes more than she does, so she could get roughly 25% of the income differential, but in their CO they agreed to no CS because DH assumed all of their debt and the debt service was far in excess of what CS would have been.  She threatened going back for CS once, but it was too soon after the divorce for her to have gotten it and when DH showed her the math she realized it was too small an amount to bother with.  Plus I was providing childcare on some of her days when I was home, and that would have ended immediately if she went for CS. After that she married a guy with a substantial income, became a SAH and hasn't mentioned CS since. 

Kids get healthcare through our state's CHIP program, through our household since BM's household now makes too much to qualify.  CO says medical is split 50/50, but the premium we pay is small so we don't bother asking BM for half.  For ECs, BM pays for what she signs the kids up for, and DH pays for the stuff he signs them up for.  It all works out, and they don't nickel and dime each other.

We dont pay or receive anything for SD, but I (am supposed to) receive $50/month for ODS.

DH pays $650 plus provides insurance at approx $120 month for SS17.  Expenses: cell, school lunches, school fees are 50/50. Medical copays split 80/20.  DH is supposed to get dependency exemption as part of child support worksheet.

On a side note:  if DH is responsible for 1/2 of school lunches do you guys think it should include meals at McDonalds/Taco Bell/BM's house?  DH has been refusing anything but actual school lunches and giving SS a bit of cash for incidentals.

My boyfriend is very lucky... His kid's mom's not so much. He pays a little less than 800 a month for 4 kids and gives the mother of his two little kids money off the books. I think it's around $400 and then buys them whatever else they need like clothes, homeschooling circ. Etc.

What does your husband pay op?

My SO pays 1/3 of his income in child support for two kids. He pays half of the children's insurance premiums because his employer doesn't offer insurance (contracted). He also pays half of out of pocket medical.

That is all he is legally ordered to pay to her. He chooses to help with other things on a case by case basis if he supports it. Such as scouts. BM did it all on her own but we like the kids being in it so we help buy the supplies as we can. He's paid money for school extras like T-Shirts and such but that's choice.

I am not legally required to pay anything for the kids and my income is not a factor. I chose to help support them in our home.

usually end up paying in some form indirectly.  The courts here changed the wording back in 2009 on the income statement asking what income is coming from all members of the household AKA anyone living with NCP dad.

The courts feel that if Dad is being helped with a live-in partner/spouse/granny/roommate on bills then that frees up his income to pay more CS.  Which is totally a travesty.  What I did was make copious copies of the OLD form which just asks about NCP dad's income.

Step Dads usually don't have to worry about this because they are 99% of the time on the recipient side living with CP BMs but I am sure they are treated like a walking ATM as well.

Also you should be well aware that the Clinton Era Social Security Act gives Fed kickbacks to local child support collection agencies for highest amount collected or decreed.

Zero incentive for download mods.

My DH paid $1200 a month for about 16 years, plus health insurance and 60% what insurance did not pay, plus 50% of braces. His CS was 1/3 of his gross pay initially, so it was a huge chunk of his monthly expense. He had EOW visitation where he drove 4 hours roundtrip on Friday to get SSs and 4 hours on Sunday taking them back, no driving by BM, so gas and tolls were an added cost. SSs were 5 and 3 when his CS order was entered, so 1 SS was in school full-time and 1 SS was in pre-school several days a week, but the CS was so high bc  BM claimed she was paying HER retired BM $800 a month for child care! (Same lady who watched them for free when DH and BM were married.) We didn't even pay that much when we had an infant in day care full-time.

When both SSs were in school full-time, DH should have gotten it reduced but instead, kept paying that amount bc he didn't want to rock the boat, so he overpaid for many years. Over time, he earned more money, but BM did not ask for more, so it evened out until oldest SS turned 18. Support should have ended for him, reducing the CS at that time, but DH KEPT PAYING the full $1200 a month to BM for two more years until youngest SS graduated from high school 6 mos after he turned 18, so BM got a huge windfall during those 2 years.  The whole thing was sickening to me and still is when I think back. The only saving grace was that DH became an owner of our law firm (as did I) and got a HUGE raise the year after all CS ended, so BM never got her claws in that money, and she never will!! 

We have separate bank accounts. We split household bills in half, as well as split the mortgage.

He has 50/50, which because she filed for head of household is technically 51/49, but we do a 5 days on/5 days off situation, and are flexible when she wants to trade days, etc.

She is supposed to cover insurance, but is currently jobless and might be on disability. We do not know and DH doesnt press the issue so as not to rock the boat.

As child has gotten older I have been doing less for meals. He does most of the cooking and grocery/food purchases when she is with us.

Currently BM Toxic Troll is "between homes", so Munchkin SD13 has been with us full time.

In our case the SpermClan (the SpermIdiot never paid a dime. SpermGrandHag and SpermGrandPa paid it for him) paid $110/mo for 2yrs then $133/mo for 9 years.  Due to his running from the process server his CS went to $785 for one year then settled at $385/mo for the final 6 years.  The SpermClan never paid a penny above CS and often paid that late.  They were supposed to pay half of all medical costs (Rx, dental, vision, copays, etc, etc, etc...) but never paid a penny of that $10K though it was COd.

His mom and I chose to provide him with a top 10% boarding school (Military School) education.  The SpermClan freaked out fearing that we would tray to nail them for additional support for the tuition. We of course could not have nailed them for tuition.  Their COd obligation (consisting of CS including a few other minor add ons)  as is the case with most Custody/Visitation/Support COs was the limit of their obligation to support the Skid.

CS was elevated to cover a portion of medical insurance and half of after school care costs ($15/mo for the NCP's share of health insurance premiums and $50/mo for the NCP's half of after school care).  The NCP also received an income reduction credit of -$1000/mo (the maximum) due to the StepDad's (my) "elevated income that provides an artificial standard of living for the child" (According to the bottom 10%er of the legal profession in the Harry Potter robes slinging the Fisher-Price wooden hammer). The income reduction credit reduced his CS by a $50/mo.  According to the Hogwarts' Professor NumbNuts Judge.... the NCP should not be punnished by having to support his child at the maximum level due to my income.  As I said... Professor NumbNuts. So, for 16+ years the SpermIdiot got a benefit from my income.  Though only $50/mo of a benefit it chapped my ass beyond all rational importance.

My wife had full physical and legal custody of SS. The SpermClan had 7wks of visitation per year (5wks summer, 1wk winter, 1wk spring)  since we never lived nearer than 1200 miles to SpermLand. 

Our CO was based in the Pac NW.  SS's visitation was always to the Pac NW.   We lived in either TX, PA or DE until SS aged out from under the CO.

Partner has a 60/40 split with his EW.  Pays (in total) over $5000/mos for CS and SS.  He has one son.  EW refuses to work, claims she is an immigrant that can’t speak English (BS).  She has a LinkedIn acct that claims to the contrary.  Has a business degree, worked in Canada for a large banking corporation etc.  

EW has even worked her immigration status to swindle a “friend of the court” and consistently harasses my partner via the courts to increase SS every time his income increases.  Meanwhile, she sits at home every day, gets her nails done and shops on his dime.

EW convinced my partner to sponsor her mother to move to Canada before they split.  He paid over $40,000 before they divorced in court fees for that as well.  So, essentially, she lives in a two bedroom condo, with her mother, shares a bed with her 12 yr old son, doesn’t work, and makes more than I do working a 40hr work week.  She also has built in babysitting and draws EI.

Thanks Canada!

I see several answers pertaining to how one would calculate CS that seem to be largely opinion based, that wasn't the question and it is irrelevant.  As any adult knows each state is going to have some formula on how it is calculated at least in the US.   Just trying to bring us back onto the Target.    

My DH has a 16 year old son, who he actually very, very rarely sees these days. Nevertheless, according to the department of child support, he officially has his son 8% of the time, because his access allotment was always every other weekend from Saturday morning to Sunday afternoon. Up until recently, he was paying $187 a week in child support. Now we've had our own baby, it's gone down a bit, to $153 a week. One tiny blessing, is that the CS gets deducted from his pay, along with tax and superannuation, before what's left lands in his account. So he doesn't miss the money he loses to CS, because he doesn't even see it.

Now, I've been a stay-at-home-mum all year, and we've all lived on just DH's wage. Which would be normally be fine. Except that he smokes a pack of cigarettes a day. Cigarettes have become outrageously expensive in Australia. A pack of 20 costs $25. So if you smoke a pack a day, that equals $175 per week, just on that.  So that makes living paycheck to paycheck very difficult.

Another interesting thing, is that when I have applied for certain handouts from the government (that I'm entitled to) they look at my whole situation, including my husband and his income. And they look at DH's wage BEFORE tax, super and CS get deducted.  HOWEVER, when The Child Support department (who is part of the government) look at my husband's situation, they don't take ME into consideration AT ALL.