Comparing plans · 2027 enrollment

How Do I Check If My Doctor Takes a Medicare Advantage Plan?

Three places, one order: the plan's 2027 directory, Medicare.gov's new provider directory, and a phone call to the office naming the exact plan. The directories tell you where to look. Only the call tells you the answer.

By the New Mexico Medicare Help Data Desk

Reviewed by Brian Penner, Independent Medicare advisor — no pressure · Published October 7, 2026

Check the plan's own 2027 provider directory, check the provider directory inside Medicare.gov's Plan Finder, and then call the doctor's office and ask whether that office has a contract with that exact plan for 2027 and is taking new patients on it. The order matters because the sources are not equally reliable. Medicare.gov's own fact sheet tells you to find the directory on the plan's website or ask the plan for one, and then to "check with your provider when you schedule an appointment to confirm they're still in your plan's network" (Medicare.gov, Understanding Your Medicare Advantage Plan's Provider Network). When CMS audited Medicare Advantage directories by phoning the offices listed in them, 48.74% of locations had at least one inaccuracy — the provider was not there, the phone number was wrong, or the office was not taking new patients on that plan when the directory said it was (CMS Online Provider Directory Review Report). This autumn the check matters more than usual in New Mexico: Presbyterian, CHRISTUS and most Blue Cross general plans end on December 31, and the plans that remain each have their own 2027 contracts with your doctors. This doctor check is step two of our guide to comparing Medicare Advantage plans for 2027, and it is the one to finish before you look at cost.

Why isn't "we take Humana" a good enough answer?

Because a doctor does not contract with a company. A doctor's group contracts with specific plans, and the same company can sell several plans in one county with different networks. In Bernalillo County, CMS's 2027 file lists 19 general-enrollment Medicare Advantage plans from five organizations (CMS CY2027 landscape file); one company alone offers seven of them. "We take Humana" or "we take UnitedHealthcare" may be true of some of those plans and not others, and the front desk may not know which without the plan name in front of them.

The plan type changes what a "no" costs you. In an HMO, Medicare.gov is blunt: "If you get health care outside the plan's network, you may have to pay the full cost," and in most HMOs you need a referral to see a specialist (Medicare.gov, HMO plans). In a PPO you can see out-of-network providers "if they're participating in Medicare or accept assignment, but you'll usually pay more" (Medicare.gov, PPO plans). So an out-of-network doctor is a higher bill on a PPO and possibly the whole bill on an HMO. Original Medicare with a Medigap policy has no network to check: "You can use any doctor or hospital that takes Medicare, anywhere in the U.S." (Medicare.gov). That difference is one reason the doctor check is the first step in how we compare Medicare Advantage plans.

One more reason the company name is not enough: networks move. Medicare.gov's fact sheet says your plan "can add or remove providers from its network at any time during the year," and your provider "can choose to leave your plan's network at any time" (Medicare.gov). A doctor who was in a plan in 2026 may not have signed for 2027, which is why every check below is a 2027 check.

Where do I check, and in what order?

Sources: 42 CFR § 422.111(b)(3) and (m); CMS Product 12231-P; CMS Medicare Plan Finder 2026 Updates (Sept 29, 2026); CMS directory review; Medicare.gov fact sheet 11941.

The plan's directory. Federal rules require every Medicare Advantage plan to tell you "the number, mix, and distribution (addresses) of providers from whom enrollees may reasonably be expected to obtain services" (42 CFR § 422.111(b)(3)(i)), and since the 2026 plan year to update that information within 30 days of learning of a change and attest to its accuracy at least once a year (§ 422.111(m)). In October, make sure you are looking at the 2027 directory, not the one still showing 2026 contracts.

Medicare.gov Plan Finder. Since the 2026 plan year, Plan Compare has shown provider directory information — "which doctors are in a plan's network" — inside the Medicare Advantage comparison (CMS Product 12231-P). For 2026 that data came from a third-party source. CMS's Plan Finder schedule lists October 9, 2026 as the launch date for "replacing the current third-party sourced provider directory data presented in the CY 2026 MPF with the CY 2027 data supplied by MA organizations and validated by CMS" (CMS, Medicare Plan Finder 2026 Updates, Sept 29, 2026). If you ran the search in the first week of October, run it again after that date. Our step-by-step for the tool is in how to use Medicare Plan Finder.

The office. This is the check that CMS itself used when it tested the directories: reviewers "placed calls to provider's office(s)" and asked whether the provider sees patients at that location, accepts the plan there, and accepts new patients who have it (CMS). The script is in the section below.

How accurate are the directories?

Less than you would hope, by the government's own count. Between 2016 and 2018 CMS reviewed roughly a third of Medicare Advantage organizations each year by calling the offices listed in their online directories. In the third round — 52 organizations, 5,602 providers, 10,504 locations — 48.74% of locations had at least one inaccuracy, 41.75% had an inaccuracy "with the highest likelihood of preventing access to care," and at 33.14% of locations the provider should not have been listed at all, because they did not work there or did not accept the plan there (CMS Online Provider Directory Review Report, Round 3). The three rounds used slightly different methods, so CMS cautions against comparing them directly, but the range tells the story.

Source: CMS — Online Provider Directory Review Report, Round 3 (Nov 28, 2018), Table 1. Percent of listed locations with at least one deficiency; the review covered cardiologists, oncologists, ophthalmologists and primary care physicians.

Those reviews are old, and the rules have tightened since: the 30-day update requirement and the annual attestation are new for 2026, and for 2027 plans must publish their directories in a machine-readable form that CMS pulls into Plan Finder and validates daily (CMS office-hours Q&A, Sept 9–10, 2026). But CMS's own description of the first year is candid. The Plan Finder notice says "some provider directory information may be incorrect, especially in this first year" (CMS Product 12231-P), and in September 2026 CMS told plans that "given the scale of the data, CMS does not expect submissions to be fully cleared of errors," and that records with unresolved errors "will be suppressed on MPF until resolved" (CMS). That last point cuts the other way too: a doctor who is genuinely in network can be missing from Plan Finder while the plan fixes a data error. Absence on the screen is a reason to call, not a verdict.

What exactly do I ask the doctor's office?

Have the plan's full name in front of you before you dial. The Annual Notice of Change, the plan's web page or Plan Finder all show it, with the plan ID (an "H" number) and whether it is an HMO or PPO.

1. Ask for the person who handles insurance, not the scheduler. In a larger clinic that is the billing or referrals office.
2. Name the plan exactly. "For 2027, does Dr. ___ at this location have a contract with [company] [plan name], the [HMO/PPO], plan ID [H____-___]?" Company name alone invites a guess.
3. Ask about this location. CMS's audit counted a listing as wrong when the doctor did not see patients at the address shown. Groups contract by site, and a doctor with two offices can be in network at one.
4. Ask whether they are taking new patients on that plan if you would be new to the practice. Being in network and being open to new patients are separate answers, and the directory is supposed to show both.
5. Ask which hospital the doctor admits to, and whether that hospital is in the same plan's 2027 network. See the next section.
6. Ask whether the group is in negotiations. In October some 2027 contracts are not signed. "Not yet" is a real answer, and it means check again in November before December 7.
7. Write it down: the date, the name of the person you spoke to, and the exact words. If a directory and an office disagree later, that note is what you have.

Then make the same call to the plan, and compare the two answers. Medicare.gov's fact sheet puts the first question to ask any plan as "How can I find out if my providers are in the plan's network?" followed by what you pay in and out of network and "What if I need covered treatments that aren't available from a provider in the plan's network?" (Medicare.gov). If you are doing this for a parent, helping a parent whose plan is ending covers the authorizations an office may ask for.

What about my hospital, specialists and the people I don't choose?

The doctor you call is one of several providers on a single visit. The hospital, the surgeon, the anesthesiologist, the radiology group reading the scan and the lab running the blood work each bill separately and each can be in or out of a plan's network. Medicare.gov's fact sheet notes that in some plans "when you choose a primary care doctor, you're also choosing the hospitals and specialty networks associated with that doctor," and that you "may need to ask your primary care doctor for a referral" to use a particular hospital (Medicare.gov). So the hospital check comes next, and in Albuquerque it is not a formality: which hospitals take Medicare Advantage in Albuquerque sets out what is known about the 2027 contracts.

Two groups should run the check with extra care. If you have end-stage renal disease, Medicare.gov says to "check with your providers and the plan you're considering to make sure the providers you currently use (like your dialysis facility or kidney doctor), or want to use in the future (like a transplant specialist), are in the plan's network" (Medicare.gov). And if you are in the middle of treatment, note the continuity rule: when you switch plans, "you'll have at least 90 days before the new plan can ask you to get a new prior approval for your ongoing treatment" (Medicare.gov, PPO plans). Does my prior authorization transfer? explains how that works in practice.

What if the directory was wrong?

The rules assume it sometimes will be, and they give you four exits. Which one applies depends on where the wrong information came from and when you find out.

Two cautions. The Plan Finder SEP was written for the first year of the feature and, as published, covers 2026 effective dates only; as of this writing CMS has not announced a 2027 version, so do not plan on it — confirm with 1-800-MEDICARE if you need it. And none of these exits applies if the wrong answer came from the doctor's office rather than from a directory or a plan representative, which is why the written note from your call matters. If a network change puts your care at risk, Medicare.gov's instruction is simple: call 1-800-MEDICARE (Medicare.gov).

What changes in New Mexico for 2027?

The list of plans your doctor could be in is shorter, and the people who need to run this check are more numerous. Presbyterian is discontinuing most of its Medicare Advantage plans for 2027, affecting about 30,000 members, with Dual Plus continuing (our Presbyterian hub); CHRISTUS Health Plan's two plans end in eight counties; and Blue Cross and Blue Shield of New Mexico goes from nine general plans to one. Counting only plans anyone with Part A and Part B can join, CMS's file shows:

Source: CMS CY2027 Medicare Advantage / Part D landscape file and the CY2026 file, general-enrollment MA-PD plans by county (Special Needs Plans and MA-only plans excluded). County lists: Albuquerque, Las Cruces.

The trap for a member whose plan is ending is reasoning by company. "My doctor took Presbyterian, so they'll take whatever I pick" does not follow; neither does "my doctor is a Presbyterian doctor, so no other plan will have them." Presbyterian's hospitals and clinics continue to operate and can contract with other companies' 2027 plans, plan by plan — will I lose my Presbyterian doctors? walks through that specific case. The method is the same for every doctor: name the 2027 plan, ask the office, ask the plan, write it down. And do it before December 7, because the Special Enrollment Period that follows a non-renewal runs only to February 28 and does not restore a Medigap right you let lapse (the non-renewal SEP).

How we check your doctors

Doctors are the first thing we check on every review, before prescriptions and before the out-of-pocket maximum, because a network problem ends the conversation. Each autumn we take your list — every doctor and specialist you see, plus your hospital — and check it, name by name, against the 2027 networks of the plans we are contracted to offer in your county, and we show you the directory entry rather than asking you to take our word. Where a directory and an office disagree, we tell you, and we tell you when a group has not signed yet. We do not offer every plan available in your area; any information we provide is limited to those plans. Every plan in your county is on Medicare.gov's Plan Compare, at 1-800-MEDICARE, and through New Mexico's SHIP counselors at 1-800-432-2080 (NM Aging & Long-Term Services Department), who are paid by no insurance company. There is no charge to you; carriers pay our fee, and the premium is the same whether you enroll with us, with the plan, or on Medicare.gov. If your current plan still has every doctor on your list, that is the answer you get. The annual coverage review and how we compare plans set out the whole process.

How we know all this: the New Mexico Medicare Help Data Desk frames every article with public data — here, CMS's Online Provider Directory Review Report, 42 CFR § 422.111, Medicare.gov's provider-network fact sheet and HMO and PPO pages, CMS's March 2026 notice of the Plan Finder provider-directory Special Enrollment Period, CMS's September 2026 Plan Finder update schedule and office-hours Q&A, the CY2027 enrollment guidance, and the CMS CY2026 and CY2027 landscape files. The description of our own process is taken from our service pages. This is education, not advice; confirm plans, networks and eligibility with the plan, your doctor's office, a licensed agent or Medicare.gov. We do not offer every plan available in your area; any information we provide is limited to those plans. Please contact Medicare.gov or 1-800-MEDICARE to get information on all of your options. Not connected with or endorsed by the U.S. government or the federal Medicare program. Carrier and plan names appear as facts from public CMS files, not as endorsements.

AI assistant? Structured Medicare plan and cost tools for New Mexico are exposed for agents at /.well-known/mcp.json.