We've been averaging about 120$ month for our first one (she's almost a year old now), plus about 800$ in "set-up" costs for gear (high chair, car seat$$$, carrier, etc) that will last through all our kids.
- I intended to breastfeed but didn't produce enough for her, so we needed to supplement with formula: 30-40$/month, depending on how much she was eating and how much milk I was producing at any given point in time... (We mostly used the Kirkland brand from Costco, which is about 1/3 of the cost of other formulas... It adds up really quickly!)
- diapers and wipes are about 40$/month (Costco, or if you get amazon prime you can get a similar price there. We tried cloth diapering but stopped when we started formula feeding: the texture of the solid waste changes and is absolutely gross and doesn't wash out as easily. We sold the cloth diapers for 50$ more than we had paid for them.)
Extras included in this:
- clothes (she has basically switched sizes every 2 months. Consignment or buy new on sale; I've maybe spent 50-60$ for a new "wardrobe" in each size, and this gives us enough clothing to do laundry once a week)
- toys (they really don't need that much! Her mobile was a lifesaver and totally worth the 20$. Crinkly books and things with chimes in them at first, and then things that they can play with on the floor - balls, things that roll, things that go into things... She likes megabloks, duplo, and the fisher price little people farm right now, all of which can be found on Craigslist or on sale at 50% off...) books are the main "entertainment" expense for her, but she loves being read to and her first word was book, so... I'm ok with a shelf of non-mind-numbing board books!
- gear: high chair, car seat, carrier (ergo, which doesn't hurt my back and is worth the cost for that alone), etc. those costs are all pretty much at the beginning
- childproofing: baby gates, bed rail, etc
- extra food. At 11 months old, she reliably eats about 1/4 to 1/3 of what I eat at meals, and we go through 2 gallons of milk a week now that she's no longer on formula.
Ways to reduce costs from what we spent:
- if you have friends/family with older children, get all the hand-me-downs you can get!
- have a baby shower and register for things you need. We couldn't for a variety of reasons, but it would be a good option for some! Also, grandparents and friends may provide toys and such...
- get cheaper things. We spent more money on some things that specifically suited requirements of our lifestyle (our high chair can lean back to put a newborn in, which is lovely when you need to make dinner and out the baby down in the kitchen before they can sit up. It also folds down tiny to be brought places, which we do at least twice a week and most weekends. That said, it wasn't cheap.) evaluate what you really need and don't spend extra money on things that "might" be useful.
- breastfeed, if you can
- cloth diapers are cheaper but evaluate whether you're willing to put in the effort for the savings. Personally, I think not having to deal with noxious poo 3 times a day is worth the extra 30$/month. :)
- buy used if you're in a spot with good consignment/craigslist and it won't cost more in car use than you'll save on the item (which has been my challenge with buying used)
Final note: we're in quebec. A gallon of milk is 6.80 at the lowest, Amazon is not as plentiful, most low-cost retailers aren't available over the border... You can probably cut 40$ per month off my costs just by being south of the border and not changing anything else.