With more than 1.4 million plans sold over the years, Florida’s prepaid tuition program is without question one of the most popular ways for families to save for future college expenses.

Florida prepaid’s open enrollment is now in full swing, and thousands more families are expected to buy prepaid contracts between now and the enrollment period’s Jan. 31 deadline.

But the plans don’t come cheap. Five years ago, pre-purchasing four years of state university schooling for your newborn in a lump sum payment cost $11,717. This year, that same plan costs $49,293. And that’s not including other college-related expenses such as housing, though parents can purchase a separate prepaid dorm plan if they wish.

“I was just, like, kind of shocked,” said Kelly Carrasco-King, a South Miami-Dade mother who already has one prepaid plan and is considering a second plan for her newborn.

While a prepaid plan can considerably reduce college costs, it is certainly not buying tomorrow’s college at today’s prices. A prepaid contract costs much more than today’s tuition rates — the $49,293 four-year university plan is more than double today’s four-year tuition cost of about $22,700.

Buyers of prepaid are betting that, 18 years from now, tuition will be above $50,000, and maybe even above $100,000, which would make that $49,293 purchase price a bargain. Families are also attracted to prepaid’s state guarantee that their investment is safe.

Florida prepaid’s exploding cost is a direct result of never-ending tuition increases at state schools. Florida universities were long among the country’s most affordable, but in recent years the schools have been hit by sizable cutbacks in state funding. One way that universities are closing that budget gap: 15 percent tuition increases that are being approved year after year.

Florida tuition is still much cheaper than the national average — the state ranks 45th, though that is up three spots from last year’s ranking.

In setting prices, Florida prepaid officials have to estimate what tuition will cost 18 years from now. Because the trend of 15 percent annual increases shows no signs of slowing down, prepaid must set much-higher prices to make sure the program can pay its future obligations.

If one assumes tuition increases of 7 percent a year — less than half the current 15 percent trend — then without the prepaid program, your newborn would have to pay more than $85,000 for four years’ tuition at a state school by the time they graduate.

In that case, the $49,293 prepaid price tag is much cheaper.

But what if tuition increases slow down, and tuition 18 years from now is less than $49,293? In that scenario, prepaid isn’t really a good deal at all. The financial information website bankrate.com highlighted this possibility in an article last year that criticized prepaid plans, and used Florida as an example. The authors found that slower-than-expected tuition increases could turn prepaid into a “money-losing investment” where you’re paying more than the future cost of college — and you’re paying for it today.

Sticker-shock has certainly discouraged some parents from buying this new, pricier version. Last year’s plan sales of 38,567, while a slight improvement from the previous year, were noticeably down from the 47,494 plans sold five years ago.

Paying off a prepaid plan through monthly installments (as opposed to a lump sum) is one way families have coped with the higher cost, but that monthly payment plan does have a drawback: an annual interest rate of 3.95 percent is tacked on. That brings the price up to $64,346 if financed over 18 years.

Though families may feel squeezed by the price increases, saving for college is still within your reach. Less-expensive options include:

•  Instead of prepaying for a four-year university plan, consider buying a two-year community college plan, which costs far less. For a newborn, these plans cost just over $8,000, and can be broken into monthly payments of $48.73 for the next 18 years. These plans are much cheaper because community college tuition is both less expensive and rising at a slower rate than state universities.

Prepaying for two years of community college doesn’t mean your child has to attend school there — prepaid plans are useable at any accredited institution, public or private. If the chosen school costs more than a Florida community college, the prepaid plan will contribute an amount equal to the current community college tuition, with the student having to pay the difference.

•  Tax-advantaged 529 plans are another good option. The plans aren’t financially backed by the state, and are therefore subject to stock market risks, but parents can structure their plan so that, as the child gets older, more of the money is invested in safe options like CDs. This is known as an age-based asset allocation plan.

Although Florida offers a 529 plan, families don’t have to invest in the state’s 529 — you can shop around through various states’ plans to find the one you like. One important consideration: choose a 529 with low administrative fees.

Should your 529 plan perform well, it could potentially generate more in college savings than a prepaid plan, and, unlike prepaid, families can choose how often — and how much — they want to contribute.

That increased flexibility also carries over to how 529s can be spent, as the accounts can pay for books or other educational expenses that prepaid doesn’t cover.

Financial aid expert Mark Kantrowitz is a big believer in 529s — he says families may get a “false sense of security” from their prepaid plans, unaware that the state has some contractual wiggle room. The fine print of Florida prepaid says that if state leaders deem the program “infeasible,” then only beneficiaries aged 13 or older could collect the full value of tuition when they enroll. Younger beneficiaries would get a refund, with interest.

Kantrowitz also says 529s can, in many cases, outperform Florida prepaid.

“529 plans, even though you’re carrying all the risk, you’re also getting all the reward,” Kantrowitz said.

Other financial planners, like Coral Gables-based Cathy Pareto, still think prepaid’s state guarantee has some value. While prepaid plans in other states have run into financial trouble, Florida’s plan — thanks to its conservative investing strategy — has a $500 million surplus.

Pareto says families with little to no investing experience are at risk of panicking when the stock market hits a serious slump. They may withdraw all their funds from a stocks-sensitive plan like a 529 — which is just about the worst possible way to react.

“People do some strange things when the markets go down, and emotions take over,” Pareto said. “They make really bad decisions, and the 529 kind of opens you up to that.”